This prospectus is part of a registration statement that we filed with the U.S. Securities and Exchange ~~Commission. You should rely only on~~Commission, or the SEC, using a “shelf” registration process. By using a shelf registration statement, we may sell securities from time to time and in one or more offerings up to a total dollar amount of $75,000,000 as described in this prospectus. Each time that we offer and sell securities, we will provide a prospectus supplement to this prospectus that contains specific information ~~we have~~about the securities being offered and sold and the specific terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement or ~~incorporated by reference~~free writing prospectus may also add, update or change information contained in this prospectus with respect to that offering. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement or free writing prospectus, you should rely on the prospectus supplement or free writing prospectus, as applicable. Before purchasing any securities, you should carefully read both this prospectus ~~supplement.~~ and the applicable prospectus supplement (and any applicable free writing prospectuses), together with the additional information described under the headings “Where You Can Find More Information” and “Incorporation by Reference.”

We have not authorized anyone to provide you with ~~additional~~any information or ~~different information. We are not making an offer of these securities in~~to make any ~~state where the offer is not permitted. You should not assume that the information in this prospectus is accurate as of any date~~representations other than ~~the date on the front of the prospectus.~~

~~You should rely only on the information~~those contained in, or incorporated by reference in, this prospectus, ~~and~~ any applicable prospectus ~~supplements. Neither Discovery Laboratories, Inc. nor~~supplement or any free writing prospectuses prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the ~~selling stockholders have authorized~~reliability of, any other ~~person to provide you with different information. If anyone provides you with different or inconsistent~~ information ~~you should~~that others may give you. We will not ~~rely on it. The Company is not making any offer to sell these securities and the selling stockholders are not making~~make an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus and the applicable prospectus supplement to this prospectus is accurate only as of the date on its respective cover, that the ~~cover page~~information appearing in any applicable free writing prospectus is accurate only as of the date of that free writing prospectus, and that ~~information contained in~~ any ~~document~~information incorporated by reference ~~in this prospectus~~ is accurate only ~~accurate~~ as of the date of the document incorporated by ~~reference.~~reference, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have ~~subsequently changed.~~

Unless the context otherwise requires, references in this prospectus to “Windtree,” “Windtree Therapeutics,” “the Company,” “we,” “our,” and “us” refer to Windtree Therapeutics, Inc., a Delaware corporation, and our consolidated subsidiaries.

We use “Windtree Therapeutics,” as our trademark, and we have been granted a trademark or have a trademark application on file with the United States Patent and Trademark Office. All trademarks or trade names referred to in this prospectus are the property of their respective owners. Solely for convenience, the trademarks and trade names in this prospectus are referred to without the ® and ™ symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. We do not intend the use or display of other companies’ trademarks and trade names to imply a relationship with, or endorsement or sponsorship of us, by any other companies.

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. The ~~following summary highlights~~SEC maintains a website that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that website is http://www.sec.gov.

Our website address is www.windtreetx.com. The information on, or that can be accessed through, our website is not part of this prospectus and is not incorporated by reference herein and you should not consider it part of this prospectus. We have included our website address as an inactive textual reference only.

This prospectus and any prospectus supplement are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Forms of the indenture and other documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement or documents incorporated by reference in the registration statement. Statements in this prospectus or any prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters.

INCORPORATION BY REFERENCE

The SEC’s rules allow us to “incorporate by reference” information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC will automatically update and supersede that information. Any statement contained in this prospectus or a previously filed document incorporated by ~~reference. While we have included what we believe~~reference will be deemed to be modified or superseded for purposes of this prospectus to the ~~most important~~extent that a statement contained in this prospectus or a subsequently filed document incorporated by reference modifies or replaces that statement.

We incorporate by reference our documents listed below and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, which we refer to as the “Exchange Act” in this prospectus, between the date of this prospectus and the termination of the offering of the securities described in this prospectus. We are not, however, incorporating by reference any documents or portions thereof, whether specifically listed below or filed in the future, that are not deemed “filed” with the SEC, including any information ~~about us~~furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K.

This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that have previously been filed with the SEC:

	●	Our Annual Report on Form 10-K for the year ended December 31, 2019 filed with the SEC on April 3, 2020;
	●	Our Quarterly Report on Form 10-Q for the quarter ended March 31, 2020 and June 30, 2020, filed with the SEC on May 13, 2020 and August 14, 2020;
	●	Our Current Reports on Form 8-K filed with the SEC on March 13, 2020, March 23, 2020, April 24, 2020, April 29, 2020, April 30, 2020, May 7, 2020, May 22, 2020, July 15, 2020 and July 23, 2020; and
	●	The description of our common stock included in our Form 8-A filed with the SEC on May 15, 2020, including any amendments or reports filed for the purpose of updating such description.

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

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You may request a copy, without charge, of any of the documents incorporated by reference in this prospectus (other than exhibits, unless they are specifically incorporated by reference in the documents) by writing or telephoning us at the following ~~summary may~~address:

Windtree Therapeutics, Inc.

2600 Kelly Road, Suite 100

Warrington, Pennsylvania 18976

(215) 488-9300
Attention: Chief Financial Officer

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus and any accompanying prospectus supplement.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, including the documents that we incorporate by reference, contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, Section 21E of the Exchange Act and the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical facts contained in this prospectus are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplate,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions, although not all forward-looking statements contain ~~all the information that may be important~~these words. These forward-looking statements include, but are not limited to, ~~you. For a complete understanding~~statements about:

	●	our estimates regarding future results of operations, financial position, research and development costs, capital requirements and our needs for additional financing;
	●	how long we can continue to fund our operations with our existing cash and cash equivalents;
	●	delays in our anticipated clinical timelines and milestones associated with COVID-19;
	●	the results, cost and timing of our preclinical studies and clinical trials, as well as the number of required trials for regulatory approval and the criteria for success in such trials;
	●	legal and regulatory developments in the U.S. and foreign countries, including any actions or advice that may affect the design, initiation, timing, continuation, progress or outcome of clinical trials or result in the need for additional clinical trials;
	●	the difficulties and expenses associated with obtaining and maintaining regulatory approval of our product candidates, and the indication and labeling under any such approval;
	●	our plans and ability to successfully execute development activities and commercialize our product candidates;
	●	risks related to manufacturing active pharmaceutical ingredients, drug product, medical devices and other materials we need;
	●	the size and growth of the potential markets for our product candidates, the rate and degree of market acceptance of our product candidates and our ability to serve those markets;
	●	the success of competing therapies and products that are or become available;
	●	our ability to limit our exposure under product liability lawsuits;
	●	our ability to obtain and maintain intellectual property protection for our product candidates;
	●	recently enacted and future legislation regarding the healthcare system, including changes to the Patient Protection and Affordable Care Act;
	●	delays, interruptions or failures in the manufacture and supply of our product candidates;
	●	the performance of third parties upon which we depend, including third-party contract research organizations, contract manufacturing organizations, contractor laboratories and independent contractors;
	●	our ability to recruit or retain key scientific, commercial or management personnel or to retain our executive officers; and
	●	our ability to maintain proper functionality and security of our internal computer and information systems and prevent or avoid cyber-attacks, malicious intrusion, breakdown, destruction, loss of data privacy or other significant disruption.

These forward-looking statements are based on management’s current expectations, estimates, forecasts and projections about our business and the industry in which we operate and management’s beliefs and assumptions and are not guarantees of future performance or development and involve known and unknown risks, uncertainties and other factors that are in some cases beyond our control. As a result, any or all of our forward-looking statements in, or incorporated by reference in, this ~~offering, you should read this entire~~ prospectus ~~carefully, including the risks of investing~~may turn out to be inaccurate. Factors that may cause actual results to differ materially from current expectations include, among other things, those factors discussed under “Risk Factors” ~~beginning~~and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” or otherwise discussed in our Annual Report on ~~page 10,~~Form 10-K for the fiscal year ended December 31, 2019, our Quarterly Reports on Form 10-Q for the quarterly periods ended March 31, 2020 and ~~the information to which we refer you~~June 30, 2020, and ~~the information incorporated into this prospectus by reference. Unless the context requires otherwise,~~ in this prospectus the terms “Discovery,” the “Company” “we,” “us” and “our” refer to Discovery Laboratories, Inc., a Delaware corporation, and its consolidated subsidiary. References to “selling stockholders” refers to the stockholders listed herein under the heading “Selling Stockholders” on page 12, who may sell sharesour other filings made from time to time ~~as described in~~with the SEC after the date of this prospectus.

~~In the U.S., we have established our own specialty respiratory critical care commercial~~identify potential product candidates, including oral and medical affairs organizations that are experienced in and will focus on neonatal indications. These organizations will be primarily responsible to effect the commercial introduction of SURFAXIN. With our established relationships and contacts in the neonatal community, we believe that we also will be able to use our commercial and medical affairs organizations to effectively introduce the AFECTAIR device for infants in the U.S. We also expect that, in the future, these teams will be able to leverage the experience and relationships that we gain with the introduction of SURFAXIN and the AFECTAIR device for infants to efficiently support the introductions of AEROSURF and SURFAXIN LS, if approved.

~~Trademark Notice~~

The selling security holders named in this prospectus may offer up to 2,340,000 shares of our common stock, which includes shares of our common stock issuable upon the exercise of warrants to purchase shares of common stock. Our common stock currently is listed on The NASDAQ Capital Market under the symbol “DSCO.” Shares of common stock that may be offered in this offering, when issued and paid for, will be fully paid and non-assessable. We will not receive any of the proceeds of sales by the selling security holders of any of the securities covered by this prospectus.

~~On February 13, 2013, we entered into a lending facility (the “Deerfield Facility”)~~RISK FACTORS

Investment in any securities offered pursuant to this prospectus and the applicable prospectus supplement involves risks. You should carefully consider the risk factors included in our Annual Report on Form 10-K filed with the ~~Deerfield Entities~~SEC for the most recent year, our Quarterly Reports on Form 10-Q and our Current Reports on Form 8-K, together with all of the other information included in this prospectus, any applicable prospectus supplement, any applicable free writing prospectus and the other information incorporated by ~~way~~reference herein and therein. These risks are not the only ones facing us. Additional risks not currently known to us or that we currently deem immaterial also may impair or harm our business, financial condition, results of operations and prospects. Statements in or portions of a ~~Facility Agreement, dated February 13, 2013 (the “Facility Agreement”) pursuant~~future document incorporated by reference in this prospectus, including, without limitation, those relating to ~~which the Deerfield Entities agreed to provide financing~~risk factors, may update and supersede statements in and portions of this prospectus or such incorporated documents. Please also refer to the ~~Company~~section entitled “Special Note Regarding Forward-Looking Statements.”

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USE OF PROCEEDS

Except as set forth in any accompanying prospectus supplement, we intend to ~~$30 million~~use the net proceeds from the sale of any securities offered under this prospectus for working capital and/or general corporate purposes. Additional information on ~~a secured basis, subject~~the use of net proceeds from the sale of securities that we may offer from time to ~~the terms and conditions~~time by this prospectus will be set forth in the ~~Facility Agreement.~~

Any amounts drawn under the Facility Agreement shall accrue interest at a rate of 8.75% per annum, which shall be payable quarterly in cash. The Company has the right to prepay any amounts owed without penalty. In addition, at the election of the holders of the notes evidencing loans under the Facility Agreement (“Notes”), the principal amounts of the Notes may be reduced to the extent that the holders elect to apply a portion of the principal amount outstanding under the Notes to satisfy the exercise price of the related Warrants (see below) upon exercise of all or a portion of the Warrants. The principal amounts outstanding under the Facility Agreement are payable in equal installments on the fourth, fifth and sixth anniversaries of the Facility Agreement; provided that the amount payable on the fourth anniversary shall be deferred for one year if either (i) the Company’s “Net Sales” (defined below) for the immediately preceding 12-month period are at least $20 million, or (ii) the Company’s “Equity Value” (defined below) is at least $200 million; and provided further, that the amount payable on the fifth anniversary (together with any amount deferred on the fourth anniversary) shall be deferred until the sixth anniversary if either (x) the Company’s “Net Sales” for the immediately preceding 12 month period are at least $30 million, or (ii) the Company’s “Equity Value” is at least $250 million. For the purposes of the foregoing deferrals of principal, “Net Sales” means, without duplication, the gross amount invoiced by or on behalf of the Company, any of its Subsidiaries or any direct or indirect assignee or licensee for products, sold globally in bona fide, arm’s length transactions, less customary deductions determined without duplication in accordance with generally accepted accounting principles; and “Equity Value” means, with respect to each measurement date, the product of (x) the number of issued and outstanding shares of common stock of the Company (the “Common Stock”) on such measurement date multiplied by (y) the per share closing price of the Common Stock on such measurement date.

Additionally, any amounts drawn under the Facility Agreement may become immediately due and payable upon (i) an “Event of Default,” as defined in the Facility Agreement, in which case the Deerfield Entities would have the right to require the Company to repay the outstanding principal amount of the loan, plus any accrued and unpaid interest thereon, or (ii) the occurrence of certain events as defined in the Facility Agreement, including the consummation of a change of control transaction or the sale of more than 50% of the Company’s assets (collectively, a “Major Transaction”).

The Facility Agreement also contains various representations and warranties and affirmative and negative covenants customary for financings of this type, including restrictions on the ability of the Company to incur additional indebtedness and grant additional liens on its assets.

In connection with the execution of the Facility Agreement, on February 13, 2013, the Company issued to the Deerfield Entities warrants to purchase an aggregate of 2,340,000 shares of the Common Stock at an exercise price of $2.81 per share of Common Stock, representing a 24% premium to the closing price of Common Stock on The NASDAQ Capital Market on the immediately preceding trading day. Following the Milestone Date and upon disbursement of the additional $20 million loan under the Facility Agreement, the Company will issue warrants to purchase an additional 4,660,000 shares of Common Stock at an exercise price of $2.81 per share of Common Stock (together with the warrants in the preceding sentence, the “Warrants”). The number of shares of Common Stock into which a Warrant is exercisable and the exercise price of any Warrant will be adjusted to reflect any stock splits, recapitalizations or similar adjustments in the number of outstanding shares of Common Stock.

The holder of a Warrant may exercise the Warrants either for cash or on a cashless basis. In connection with a Major Transaction, as defined in the Warrants, to the extent of consideration payable to stockholders in cash in connection with such Major Transaction, the holder may have the option to redeem the Warrant or that portion of the Warrant for cash in an amount equal to the Black-Scholes value (as defined in the Warrant) of the Warrant or that portion of the Warrant redeemed. In addition, in connection with a Major Transaction, to the extent of any consideration payable to stockholders in securities, or in the event of an Event of Default, the holder may have the option to exercise the Warrant and receive therefor that number of shares of Common Stock that equals the Black Scholes value of the Warrant or that portion of the Warrant exercised. Prior to the holder exercising the Warrant for shares in such transactions, the Company may elect to terminate the Warrant or that portion of the Warrant and pay the holder cash in an amount equal to the Black Scholes value of the Warrant.

In connection with the Financing, the Company entered into a Registration Rights Agreement with the Deerfield Entities (the “Registration Rights Agreement”) obligating the Company to register for resale the shares of Common Stock issuable upon the exercise of the Warrants or shares issued in connection with an event of default or repayment of the facility pursuant to the terms of the Facility Agreement on a registration statement on Form S-3 to be filed with the Securities and Exchange Commission within 60 days after the applicable Warrants are issued.

The Company has also entered into a Security Agreement with the Deerfield Entities (the “Security Agreement”), pursuant to which, as security for the Company’s repayment of its obligations under the Facility Agreement, the Company granted to the Deerfield Entities a security interest in substantially all of its assets.

~~The foregoing summary of the Deerfield Facility~~ our capital stockdoes not purport to be complete and is subject to, and qualified in its entirety by ~~reference~~, our Amended and Restated Certificate of Incorporation, as amended, or the Certificate of Incorporation,and Amended and Restated By-Laws, or the By-Laws, which have been publicly filed with the SEC. See “Where You Can Find More Information.” For a complete description, you should refer to ~~the Facility Agreement, the Registration Rights Agreement, the Form~~our Certificate of ~~Warrant~~Incorporation and ~~the Security Agreement,~~By-Laws, copies of which ~~have been filed or~~are incorporated by reference as exhibits to the registration statement of which this prospectus is a part.

~~The market price~~terms of our common stock ~~like that of many other development stage pharmaceutical or biotechnology companies, has been~~ and ~~is likely to continue to be volatile. In addition to general economic, political and market conditions, the price and trading volume of our~~preferred stock ~~could fluctuate widely in response to many factors, including:~~

In the past, following periods of volatility in the market price of the securities of companies in our industry, securities class action litigation has often been instituted against companies in our industry. Even if securities class actions that we may face in the future are ultimately determined to be meritless or unsuccessful, they involve substantial costs and a diversion of management attention and resources, which could negatively impact our business.

Any issuance of equity we may undertake in the future to raise additional capital could cause the price of our common stock to decline, or require us to issue shares at a price that is lower than that paid by holders of our common stock in the past, which would result in those newly issued shares being dilutive. If we obtain funds through a credit facility or through the issuance of debt or preferred securities, these securities would likely have rights senior to your rights as a common shareholder, which could impair the value of our common stock.

We cannot predict whether future issuances of shares of our common stock or the availability of shares for resale in the open market will decrease the market price per share of our common stock. Sales of substantial amounts of our shares of common stock in the public market, or even the perception that such sales might occur, could adversely affect the market price of the shares of our common stock.

We intend that all forward-looking statements be subject to the safe-harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements are subject to many risks and uncertainties that could cause actual results to differ materially from any future results expressed or implied by the forward-looking statements. We caution you therefore against relying on any of these forward-looking statements. They are neither statements of historical fact nor guarantees or assurances of future performance. Examples of the risks and uncertainties include, but are not limited to:

Pharmaceutical, biotechnology and medical technology companies have suffered significant setbacks in advanced clinical trials, even after obtaining promising earlier trial results. Data obtained from such clinical trials are susceptible to varying interpretations, which could delay, limit or prevent regulatory approval. After gaining approval of a drug product, pharmaceutical and biotechnology companies face considerable challenges in marketing and distributing their products, and may never become profitable.

The forward-looking statements contained in this report or the documents incorporated by reference herein speak only as of their respective dates. Factors or events that could cause our actual results to differ may emerge from time to time and it is not possible for us to predict them all. Except to the extent required by applicable laws, rules or regulations, we do not undertake any obligation to publicly update any forward-looking statements or to publicly announce revisions to any of the forward-looking statements, whether as a result of new information, future events or otherwise.

~~We will not receive any proceeds from the sales of common stock by the Deerfield Entities pursuant to this prospectus.~~

This prospectus relates to the resale by the selling stockholders of shares of common stock that we may issue upon exercise of the Warrants we issued to the Deerfield Entities. We are filing the registration statement of which this prospectus is a part pursuant to the provisions of the Registration Rights Agreement we entered into with the Deerfield Entities on February 13, 2013.

~~The selling stockholders may from time to time offer and sell pursuant to this prospectus any or all of the shares that they acquire upon exercise of the Warrants.~~

The following table presents information regarding the Deerfield Entities and the shares that any of the Deerfield Entities may offer and sell from time to time under this prospectus. This table is prepared based on information supplied to us by the selling stockholders, and reflects holdings as of April 8, 2013. As used in this prospectus, the term “selling stockholder” includes the Deerfield Entities and any donees, pledges, transferees or other successors in interest of the Deerfield Entities. The number of shares in the column “Number of Shares Being Offered” represents all of the shares that the selling stockholders may offer under this prospectus. The selling stockholders may sell some, all or none of its shares. We do not know how long the selling stockholders will hold the shares before selling them, and we currently have no agreements, arrangements or understandings with the selling stockholders regarding the sale of any of the shares.

block trades in which the broker-dealer will attempt to sell the shares as agent, but may position and resell a portion of the block as principal to facilitate the transaction; purchases by a broker-dealer as principal and resale by the broker-dealer for its account; an exchange distribution in accordance with the rules of the applicable exchange; privately negotiated transactions; short sales; through the writing or settlement of options or other hedging transactions, whether through an options exchange or otherwise; broker-dealers may agree with the selling stockholders to sell a specified number of such shares at a stipulated price per share; a combination of any such methods of sale; and any other method permitted pursuant to applicable law.

This description of our common stock is a summary. You should keep in mind, however, that it is our Restated Certificate of Incorporation and our By-Laws, and not this summary, which define any rights you may acquire as a stockholder. There may be other provisions in such documents which are also important to you. You should read such documents for a full description of the terms of our capital stock, along with the applicable provisions of Delaware law.

~~We currently have authorized 100 million shares of common stock, par value $0.001 per share. As of April 8, 2013, there were 43,764,737 shares of common stock outstanding, which does not include:~~

outstanding. Subject to any preferential rights of any preferred stock created by our board of directors, or the Board, ~~of Directors, as a holder~~holders of our common stock ~~you~~ are entitled to such dividends, if any, as our Board ~~of Directors~~ may declare from time to time out of funds that we can legally use to pay dividends. ~~The holders of common stock possess exclusive voting rights, except to the extent our Board of Directors specifies voting power for any preferred stock that, in the future, may be issued.~~

~~As a holder~~

Holders of our common stock ~~you~~ are entitled to one vote for each share of common stock and do not have any right to cumulate votes in the election of directors. Upon our liquidation, dissolution or winding-up, ~~you~~holders of our common stock will be entitled to receive on a proportionate basis any assets remaining after provision for payment of creditors and after payment of any liquidation preferences to holders of preferred stock. Holders of our common stock have no preemptive rights and no conversion rights or other subscription rights. There are no redemption or sinking fund provisions applicable to our common stock. All the outstanding shares of common stock are, and the shares offered by this prospectus, when issued and paid for, will be, validly issued, fully paid and nonassessable. ~~Our~~The rights and privileges of the holders of our common stock ~~is quoted on The NASDAQ Capital Market under~~are subject to and may be adversely effected by the ~~symbol “DSCO”.~~

~~The summary description~~rights of the ~~Rights set out herein does not purport to be complete,~~holders of shares of any series of preferred stock that we may issue.

Preferred Stock

Our Board may divide the preferred stock into any number of series, fix the designation and ~~is qualified~~number of shares of each such series, and determine or change the designation, relative rights, preferences and limitations of any series of preferred stock. The issuance of preferred stock, while providing flexibility in ~~its entirety by reference to~~connection with possible acquisitions and other corporate purposes, could, among other things, have the ~~terms~~effect of delaying, deferring or preventing a change in our control and ~~provisions~~may adversely affect the market price of the common stock and the voting and other rights of the holders of our ~~Shareholder Rights Agreement, dated as~~common stock.

Common Stock Warrants

May 2020 Warrants

On May 22, 2020, we completed a registered public offering for the purchase of ~~February 6, 2004 (Certain values in the following discussion gave been adjusted to give effect to a 1-for-15 reverse stock split that was effected in December 2010).~~

~~On February 6, 2004, our Board~~an aggregate of ~~Directors adopted a shareholder rights agreement (the Rights Agreement). Pursuant to the Rights Agreement our Board of Directors~~3,172,413 units consisting of: (i) ~~declared that each stockholder of record as of the close of business on February 6, 2004, would be issued a dividend of~~ one ~~preferred stock purchase right (a Right) for each~~ share of our common stock ~~held by such stockholder~~ and (ii) ~~determined that each share of common stock issued by us after such date through the Final Expiration Date (as defined below) shall be issued with~~ a ~~tandem Right. Each Right represents the right~~warrant to purchase ~~fifteen ten-thousandths (0.0015) of a share of our Series A Junior Participating Cumulative Preferred Stock (Series A Preferred) at an exercise price equal to $50 per~~ one ~~ten-thousandths of a share (as the same may be adjusted, the Exercise Price). The Rights shall be evidenced by certificates for our common stock until the earlier to occur of:~~

The Rights are not exercisable until the Distribution Date. Until a Right is exercised, the holder thereof, as such, will have no rights as a Discovery stockholder, including, without limitation, the right to vote or to receive dividends.

~~The Rights will expire upon the close of business on February 6, 2014 (the “Final Expiration Date”), unless the Rights are earlier redeemed or exchanged by us, in each case as described below.~~

The shares of Series A Preferred purchasable upon exercise of the Rights will be entitled, when, as and if declared, to a minimum preferential quarterly dividend payment of 10,000 times the per share amount of dividends declared on our common stock. If no common stock dividend is declared in a quarter, a preferred stock quarterly dividend of $1.00 per share will be required. Upon our liquidation, holders of Series A Preferred will be entitled to a preferential distribution payment of at least 10,000 times the payment made per share of common stock. Each share of Series A Preferred will entitle the holder to 10,000 votes, voting together with our common stock. Upon any merger, consolidation or other transaction in which shares of our common stock are converted or exchanged, the holders of Series A Preferred will be entitled to receive 10,000 times the amount of consideration received per share of our common stock at an exercise price per share of common stock equal to $7.975, or the May 2020 warrants. As of September 17, 2020, there are 3,154,663 May 2020 warrants currently outstanding. The May 2020 warrants were immediately exercisable upon issuance, in ~~respect of~~whole or in part, and expire on May 22, 2025. The May 2020 warrants may not be exercised to the extent that, following such ~~transaction. The Rights are protected by customary anti-dilution provisions.~~

~~Because~~exercise, the holder would beneficially own more than 4.99% (or, at the election of the ~~nature~~purchaser prior to the date of issuance, 9.99%) of our outstanding shares of common stock, except that upon at least sixty-one (61) days’ prior notice from the holder to us, the holder may increase the amount of ownership of outstanding stock after exercising the holder’s May 2020 warrants up to 9.99% (or up to 19.99% upon prior written approval of the Series A Preferred dividend and liquidation rights, the fair market value of each one ten-thousandths of a share of Series A Preferred purchasable upon exercise of each Right should approximate the fair market value of one share of our common stock. If any person or group of affiliated or associated persons becomes an Acquiring Person, each holder of a Right, (other than Rights beneficially owned by the Acquiring Person, which become void), will have the right to receive upon exercise and paymentCompany) of the ~~then current Exercise Price, that~~ number of shares of our common stock ~~having~~outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the May 2020 warrants. The May 2020 warrants contain customary provisions that adjust the exercise price and the number of shares in the event of a ~~market value~~corporate transaction.

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December 2019 Private Placement Warrants

On December 6, 2019, we completed a private placement offering with select institutional investors for the ~~Exercise Price.~~

~~If, after a person or group has become~~purchase of an ~~Acquiring Person,~~aggregate of 2,916,666 shares of common stock and we ~~are acquired in a merger or other business combination transaction, or 50% or more~~issued Series I Warrants to purchase up to 1,458,333 shares of our ~~consolidated assets~~common stock, at an exercise price equal to $12.09 per share, or ~~earning power are sold, proper provision will~~the Series I Warrant Shares. The Series I Warrants may be ~~made so~~exercised on the six-month anniversary of the date of issuance and through the 5-year anniversary of the date of issuance. The Series I Warrants may be exercised for cash or on a cashless basis if there is no effective registration statement registering the resale of the Series I Warrant Shares and may not be exercised to the extent that the holder thereof would, following such exercise or conversion, beneficially own more than 4.99% (or such other percent as designated by each holder not to exceed 19.99%) of our outstanding shares of common stock. The Series I Warrants contain customary provisions that adjust the exercise price and the number of Series I Warrant Shares in the event of a ~~Right (other~~corporate transaction. On May 6, 2020, we entered into an amendment with certain holders of our Series I Warrants pursuant to which the exercise price of the Series I Warrant was amended from $12.09 to $9.67 if the Series I Warrant is exercised, in whole or in part, prior to December 5, 2021.

December 2018 Private Placement Warrants

On December 21, 2018, we completed a private placement offering with select institutional investors for the purchase of an aggregate of 3,928,513 shares of our common stock. In connection with this financing, we issued (i) Series F Warrants to purchase an aggregate of 667,847 shares of common stock, at an exercise price equal to $11.04 per share, which are exercisable through the 18-month anniversary of the date of issuance, or the Series F Warrants, and (ii) Series G Warrants to purchase an aggregate of 1,296,410 shares of common stock, at an exercise price equal to $12.15 per share, which are exercisable through the 5-year anniversary of the date of issuance, or the Series G Warrants and, together with the Series F Warrants, the December 2018 Warrants. The December 2018 Warrants (i) may not be exercised to the extent that, following such exercise, the holder would beneficially own more than ~~Rights beneficially owned~~9.99% (or other percent as designated by ~~an Acquiring Person, which become void) will thereafter have~~each holder) of our outstanding shares of common stock, and (ii) otherwise contain customary provisions that adjust the ~~right to receive, upon~~ exercise atprice and the ~~then current Exercise Price, that~~ number of shares of common stock into which they may be exercised in the event of a corporate transaction. On April 24, 2020, we entered into an amendment with the holders of our Series F Warrants whereby the expiration date of the ~~person~~Series F Warrant was extended from June 24, 2020 to December 24, 2020.

AEROSURF Warrants (December 2018)

In connection with ~~whom we engaged~~our acquisition of CVie Investments Limited, an exempted company with limited liability incorporated under the laws of the Cayman Islands, our Board declared a dividend to the holders of record of our outstanding shares of common stock, and holders of certain warrants to purchase common stock, that were outstanding on December 20, 2018 of 0.6148 Series H (AEROSURF) Warrant, for each share of common stock held by a shareholder or each warrant held by a warrant holder, as applicable, on the record date, or the AEROSURF Warrants. The Company expects to distribute AEROSURF Warrants that are exercisable for an aggregate of 987,722 shares of common stock. Each AEROSURF Warrant has a term of five years and provides for automatic exercise into one share of common stock, without any exercise price, upon the Company’s public announcement of the dosing of the first human subject enrolled in the ~~foregoing transaction (or its parent),~~Company’s phase 3 clinical trial for AEROSURF.

Battelle Collaboration Agreement Warrants (October 2014 and December 2018)

We entered into the Battelle Collaboration Agreement with Battelle Memorial Institute, or Battelle, in October 2014, which atwas amended in August 2015 and March 2016, for the ~~time~~development of ~~such transaction will have~~ a market value of two times the Exercise Price. In lieu of exercise, our Board of Directors may exchange the Rights (other than Rights owned by an Acquiring Person, which become void), in whole or in part, for such securities or other property or rights as the Board may determine, including any class or seriesnew version of our ADS. In connection with the Battelle Collaboration Agreement, on October 10, 2014, we issued to Battelle warrants to purchase 1,190 shares of common stock, ~~or preferred stock.~~

~~At any time before the time an Acquiring Person becomes such, our Board of Directors may redeem the Rights in whole, but not in part,~~exercisable at a price of ~~$.015~~$4,200.00 per ~~Right, subject~~share, which expire on October 10, 2024. In December 2018, we and Battelle entered into the Battelle Payment Restructuring, which reflected the terms of an October 2017 nonbinding memorandum of understanding, in which we outlined terms to ~~adjustment.~~restructure approximately $4.3 million then due to Battelle, under a Research and Development Services Agreement dated as of June 22, 2012 and the Battelle Collaboration Agreement. In connection with the Battelle Payment Restructuring, on December 11, 2018, we issued to Battelle warrants to purchase 25,000 shares of common stock, exercisable at a price of $19.50 per share, which expire on December 7, 2023.

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Panacea Venture Management Company Ltd. Warrants (July 2018)

On July 2, 2018, we issued to Panacea Venture Management Company Ltd., or Panacea, a Secured Convertible Promissory Note, or the Panacea Note, with respect to a loan facility in the aggregate amount of up to $1.5 million, which was funded in two loans of $1.0 million on the date of the Panacea Note and $0.5 million on July 23, 2018. In connection with the Panacea Note, we issued to Panacea warrants, or the Series D Warrants, to purchase 62,500 shares, or the Series D Warrant Shares, at an exercise price of $12.00 per Series D Warrant Share, or the Exercise Price. The Series D Warrants may ~~amend~~be exercised at any time beginning six months after the ~~Rights~~date of issuance and through the fifth anniversary of the date of issuance. The Series D Warrants may not be exercised to the extent that the holder thereof would, following such exercise, beneficially own more than 9.99% (or such other percent as designated by each holder) of the Company’s outstanding shares of common stock, which percentage may be increased, decreased or waived by such holder upon sixty-one (61) days’ notice to us. The Series D Warrants also contain customary provisions that adjust the Exercise Price and on the ~~conditions set out~~number of Series D Warrant Shares in the ~~Rights Agreement.~~event of a corporate transaction.

LPH II Warrants (April 2018)

On March 30, 2018, LPH II Investments Ltd. invested $2.6 million in us and acquired 180,555 shares of common stock and 45,139 Series C Warrants to purchase 45,139 shares of common stock, at an exercise price of $16.56 per Series C Warrant Share. The Series C Warrants may be exercised at any time beginning six months after the date of issuance and through the seventh anniversary of the date of issuance. The Series C Warrants may be exercised for cash or on a cashless basis if there is no effective registration statement registering the resale of the Series C Warrant Shares and may not be exercised to the extent that the holder thereof would, following such exercise, beneficially own more than 9.99% (or such other percent as designated by each holder) of the Company’s outstanding shares of common stock, which percentage may be increased, decreased or waived by such holder upon sixty-one (61) days’ notice to us. The Series C Warrants also contain customary provisions that adjust the exercise price and the number of Series C Warrant Shares in the event of a corporate transaction.

February 2017 Private Placement Warrants

On February 15, 2017, we completed a private placement offering of 2,349 Series A Convertible Preferred Stock units. Each unit consisted of: (i) one share of Series A Convertible Preferred Stock, par value $0.001 per share; and (ii) 16 Series A-1 Warrants to purchase one share of common stock at an exercise price equal to $82.20 per share. As of September 17, 2020, there are 117,485 Series A-1 Warrants currently outstanding. The Series A-1 Warrants may be exercised at any time beginning six months after the date of issuance and through the seventh anniversary of the date of issuance. The Series A-1 Warrants may not be converted or exercised to the extent that the holder would, following such exercise or conversion, beneficially own more than 9.99% (or other lesser percent as designated by each holder) of our outstanding shares of common stock.

July 2015 Warrants

On July 22, 2015, we completed a registered public offering of 29,861 Series A units and 50,000 Series B units. Each Series A unit consisted of one share of common stock and a Series A warrant to purchase one share of common stock at an exercise price of $588.00 per share. Each Series B unit consisted of a fully paid pre-funded Series B warrant to purchase one share of common stock at an exercise price of $504.00 per share, and a Series B warrant to purchase one share of common stock at an exercise price of $588.00 per share. As of December 31, 2017, all pre-funded Series B warrants were exercised. The Series A and Series B warrants, collectively the July 2015 Warrants, are exercisable immediately through the seventh anniversary of the date of issuance. The July 2015 Warrants may not be exercised to the extent that the holder would, following such exercise, beneficially own more than 9.99% (or 4.99% as may be elected by each holder) of our outstanding shares of common stock.

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Anti-Takeover Effects of Provisions

of the General Corporation Law of the State of Delaware, our Certificate of Incorporation and our By-Laws

Certificate of Incorporation and By-Laws

Because our stockholders do not have cumulative voting rights, our stockholders holding a majority of the voting power of our shares of common stock outstanding will be able to elect all of our directors. According to Section 242 of the General Corporation Law of the State of Delaware, or the DGCL, and our By-Laws, the affirmative vote of holders of at least a majority of the voting power of all of the then outstanding shares of voting stock, voting as a single class, is required to amend certain provisions of our Certificate of Incorporation. Further, our By-Laws provide that stockholder actions may be effected at a duly called meeting of stockholders or by written consent.

Our By-Laws further provide the Board with the exclusive right to increase or decrease the size of the Board (not less than three), and with the right to elect directors to fill a vacancy created by the expansion of the Board or the resignation, death or removal of a director.

Section 203 of the DGCL

As a corporation organized under the laws of the State of Delaware, we are subject to Section 203 of the ~~General Corporation Law of the State of Delaware,~~DGCL, which restricts our ability to enter into business combinations with an interested stockholder, ~~or a stockholder owning~~the owner of 15% or more of ~~our outstanding~~the corporation’s voting stock, or ~~that~~an interested stockholder’s affiliates or associates, for a period of three ~~years.~~years after such person became an interested stockholder. These restrictions do not apply if:

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●

before becoming an interested stockholder, our Board approves either the business combination or the transaction in which the stockholder becomes an interested stockholder;

●

upon consummation of the transaction in which the stockholder becomes an interested stockholder, the interested stockholder owns at least 85% of our voting stock outstanding at the time the transaction commenced, subject to exceptions; or

●

on or after the date a stockholder becomes an interested stockholder, the business combination is both approved by our Board and authorized at an annual or special meeting of our stockholders by the affirmative vote of at least two-thirds of the outstanding voting stock not owned by the interested stockholder.

Choice of ~~Contents~~

· ~~before becoming an interested stockholder, our Board~~Forum

Our Certificate of ~~Directors approves either~~Incorporation provides that, the ~~business combination or the transaction in which the stockholder becomes an interested stockholder;~~

· ~~upon consummation~~Court of Chancery of the ~~transaction in which~~State of Delaware will be the ~~stockholder becomes an interested stockholder, the interested stockholder owns at least 85%~~sole and exclusive forum for: (i) any derivative action or proceeding brought on behalf of us; (ii) any action asserting a claim of breach of a fiduciary duty owed by any of our ~~voting stock outstanding at~~directors, officers to us or our stockholders; (iii) any action asserting a claim against us arising pursuant to any provision of the ~~time the transaction commenced, subject to exceptions;~~DGCL or

· on Certificate of Incorporation or ~~after the date~~By-Laws; or (iv) any action asserting a ~~stockholder becomes an interested stockholder, the business combination is both approved by our Board of Directors and authorized at an annual or special meeting of our stockholders~~claim against us governed by the ~~affirmative vote~~internal affairs doctrine. The exclusive forum provision in our Certificate of ~~at least two-thirds~~Incorporation shall not apply to any actions or proceedings brought against us under the Securities Act or Exchange Act, whereby the U.S. District Court for the District of Delaware shall be the sole and exclusive forum.

Limitations of Liability and Indemnification Matters

Pursuant to our By-Laws, we indemnify our directors to the maximum extent permissible under the DGCL. In addition, we have entered into indemnity agreements with our officers and directors that provide, among other things, that we will indemnify them, under the circumstances and to the extent provided for therein, for expenses, damages, judgments, fines and settlements he or she may be required to pay in actions or proceedings to which he or she is or may be made a party by reason of his or her position as a director, officer, or other agent of ours, and otherwise to the fullest extent permitted under the DGCL and our By-Laws. These provisions may be held not to be enforceable for violations of the ~~outstanding voting stock not owned by the interested stockholder.~~

~~Number of Directors; Removal~~

Our By-Laws provide that our Board of Directors shall consist of at least three directors and may consist of such larger number as may be determined, from time-to-time, by the Board of Directors. Our By-laws provide that directors may be removed with or without cause by the affirmative vote of holders of a majorityfederal securities laws of the ~~total voting power of all outstanding securities.~~

~~This provision and~~U.S.

Listing

Our common stock is listed on the ~~Board of Directors’ right to issue shares of our preferred stock from time to time, in one or more classes or series without stockholder approval are intended to enhance~~Nasdaq Capital Market under the likelihood of continuity and stability in the composition of the policies formulated by our Board of Directors. These provisions are also intended to discourage some tactics that may be used in proxy fights.

symbol “WINT.”

Transfer Agent and Registrar

The ~~Transfer Agent~~transfer agent and ~~Registrar~~registrar for our common stock is Continental Stock Transfer & Trust Company.

EX~~PERT~~S

The transfer agent and registrar’s address is 1 State Street, 30^th Floor, New York, New York 10004.

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DESCRIPTION OF DEBT SECURITIES

The following description, together with the additional information we include in any applicable prospectus supplement or free writing prospectus, summarizes certain general terms and provisions of the debt securities that we may offer under this prospectus. When we offer to sell a particular series of debt securities, we will describe the specific terms of the series in a supplement to this prospectus. We will also indicate in the supplement to what extent the general terms and provisions described in this prospectus apply to a particular series of debt securities.

We may issue debt securities either separately, or together with, or upon the conversion or exercise of or in exchange for, other securities described in this prospectus. Debt securities may be our senior, senior subordinated or subordinated obligations and, unless otherwise specified in a supplement to this prospectus, the debt securities will be our direct, unsecured obligations and may be issued in one or more series.

The debt securities will be issued under an indenture between us and a third party to be identified therein, as trustee. We have summarized select portions of the indenture below. The summary is not complete. The form of the indenture has been filed as an exhibit to the registration statement and you should read the indenture for provisions that may be important to you. In the summary below, we have included references to the section numbers of the indenture so that you can easily locate these provisions. Capitalized terms used in the summary and not defined herein have the meanings specified in the indenture.

As used in this section only, “Windtree,” “Windtree Therapeutics,” “the Company,” “we,” “our” or “us” refer to Windtree Therapeutics, Inc., a Delaware corporation excluding our consolidated subsidiaries, unless expressly stated or the context otherwise requires.

General

The terms of each series of debt securities will be established by or pursuant to a resolution of our Board and set forth or determined in the manner provided in a resolution of our Board, in an officer’s certificate or by a supplemental indenture. (Section 2.2) The particular terms of each series of debt securities will be described in a prospectus supplement relating to such series (including any pricing supplement or term sheet).

We can issue an unlimited amount of debt securities under the indenture that may be issued in one or more series. Unless otherwise set forth in a resolution of our Board, in an officer’s certificate or by a supplemental indenture detailing the adoption of a series of debt securities, all securities in a series shall be identical. Debt securities may differ between series with respect to any term, provided, that all series of debt securities shall be equally and ratably entitled to the benefits of the indenture. (Section 2.1) We will set forth in a prospectus supplement (including any pricing supplement or term sheet) relating to any series of debt securities being offered, the aggregate principal amount and the following terms of the debt securities, if applicable:

	●	the title and ranking of the debt securities (including the terms of any subordination provisions);
	●	the price or prices (expressed as a percentage of the principal amount) at which we will sell the debt securities;
	●	any limit on the aggregate principal amount of the debt securities;
	●	the date or dates on which the principal of the securities of the series is payable;
	●	the interest rate or rates (which may be fixed or variable) per annum or, if applicable, the method used to determine such interest rate or rates (including any commodity, commodity index, stock exchange index or financial index) at which the debt securities will bear interest, the date or dates from which interest, if any, will accrue, the date or dates on which interest, if any, will commence and be payable and any regular record date for the interest payable on any interest payment date;
	●	the place or places where principal of, premium, if any, and interest, if any, is payable on the debt securities (and the method of such payment), where the securities of such series may be surrendered for registration of transfer or exchange, and where notices and demands to us in respect of the debt securities may be delivered;
	●	the period or periods within which, the price or prices at which and the terms and conditions upon which we may redeem the debt securities;

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	●	any obligation we have to redeem or purchase the debt securities pursuant to any sinking fund or analogous provisions or at the option of a holder of debt securities and the period or periods within which, the price or prices at which and in the terms and conditions upon which securities of the series shall be redeemed or purchased, in whole or in part, pursuant to such obligation;
	●	the dates on which and the price or prices at which we will repurchase debt securities at the option of the holders of debt securities and other detailed terms and provisions of these repurchase obligations;
	●	the denominations in which the debt securities will be issued, if other than denominations of $1,000 and any integral multiple thereof;
	●	whether the debt securities will be issued in the form of certificated debt securities or global debt securities;
	●	the portion of principal amount of the debt securities payable upon declaration of acceleration of the maturity date, if other than the principal amount;
	●	the currency of denomination of the debt securities, which may be United States Dollars or any foreign currency, and if such currency of denomination is a composite currency, the agency or organization, if any, responsible for overseeing such composite currency;
	●	the designation of the currency, currencies or currency units in which payment of principal of, premium and interest on the debt securities will be made;
	●	if payments of principal of, premium, if any, or interest, if any, on the debt securities will be made in one or more currencies or currency units other than that or those in which the debt securities are denominated, the manner in which the exchange rate with respect to these payments will be determined;
	●	the manner in which the amounts of payment of principal of, premium, if any, or interest, if any, on the debt securities will be determined, if these amounts may be determined by reference to an index based on a currency or currencies or by reference to a commodity, commodity index, stock exchange index or financial index;
	●	any provisions relating to any security provided for the debt securities;
	●	any addition to, deletion of or change in the Events of Default described in this prospectus or in the indenture with respect to the debt securities and any change in the acceleration provisions described in this prospectus or in the indenture with respect to the debt securities;
	●	any addition to, deletion of or change in the covenants described in this prospectus or in the indenture with respect to the debt securities;
	●	any depositaries, interest rate calculation agents, exchange rate calculation agents or other agents with respect to the debt securities;
	●	the provisions, if any, relating to conversion or exchange of any debt securities of such series, including if applicable, the conversion or exchange price and period, provisions as to whether conversion or exchange will be mandatory, the events requiring an adjustment of the conversion or exchange price and provisions affecting conversion or exchange;
	●	any other terms of the debt securities, which may supplement, modify or delete any provision of the indenture as it applies to that series, including any terms that may be required under applicable law or regulations or advisable in connection with the marketing of the securities; and
	●	whether any of our direct or indirect subsidiaries will guarantee the debt securities of that series, including the terms of subordination, if any, of such guarantees. (Section 2.2)

We may issue debt securities that provide for an amount less than their stated principal amount to be due and payable upon declaration of acceleration of their maturity pursuant to the terms of the indenture. We will provide you with information on the federal income tax considerations and other special considerations applicable to any of these debt securities in the applicable prospectus supplement.

If we denominate the purchase price of any of the debt securities in a foreign currency or currencies or a foreign currency unit or units, or if the principal of and any premium and interest on any series of debt securities is payable in a foreign currency or currencies or a foreign currency unit or units, we will provide you with information on the restrictions, elections, general tax considerations, specific terms and other information with respect to that issue of debt securities and such foreign currency or currencies or foreign currency unit or units in the applicable prospectus supplement.

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Transfer and Exchange

Each debt security will be represented by either one or more global securities registered in the name of The Depository Trust Company, or the Depositary, or a nominee of the Depositary (we will refer to any debt security represented by a global debt security as a “book-entry debt security”), or a certificate issued in definitive registered form (we will refer to any debt security represented by a certificated security as a “certificated debt security”) as set forth in the applicable prospectus supplement. Except as set forth under the heading “Global Debt Securities and Book-Entry System” below, book-entry debt securities will not be issuable in certificated form.

Certificated Debt Securities. You may transfer or exchange certificated debt securities at any office we maintain for this purpose in accordance with the terms of the indenture. (Section 2.4) No service charge will be made for any transfer or exchange of certificated debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with a transfer or exchange. (Section 2.7)

You may effect the transfer of certificated debt securities and the right to receive the principal of, premium and interest on certificated debt securities only by surrendering the certificate representing those certificated debt securities and either reissuance by us or the trustee of the certificate to the new holder or the issuance by us or the trustee of a new certificate to the new holder. (Section 2.7)

Global Debt Securities and Book-Entry System. Each global debt security representing book-entry debt securities will be deposited with, or on behalf of, the Depositary, and registered in the name of the Depositary or a nominee of the Depositary. Please see “Global Securities.”

Covenants

Unless otherwise indicated in this prospectus or the applicable prospectus supplement, our debt securities may not have the benefit of any covenant that limits or restricts our business or operations, the pledging of our assets or the incurrence by us of indebtedness. We will describe in the applicable prospectus supplement any restrictive covenants applicable to any issue of debt securities. (Article IV)

No Protection in the Event of a Change of Control

Unless we state otherwise in the applicable prospectus supplement, the debt securities will not contain any provisions which may afford holders of the debt securities protection in the event we have a change in control or in the event of a highly leveraged transaction (whether or not such transaction results in a change in control) which could adversely affect holders of debt securities.

Consolidation, Merger and Sale of Assets

We may not consolidate with or merge with or into, or convey, transfer or lease all or substantially all of our properties and assets to any person (a “successor person”) unless:

	●	we are the surviving corporation or the successor person (if other than us) is a corporation organized and validly existing under the laws of any U.S. domestic jurisdiction or a corporation or comparable legal entity organized under the laws of a foreign jurisdiction and expressly assumes our obligations on the debt securities and under the indenture; and
	●	immediately after giving effect to the transaction, no Default or Event of Default, shall have occurred and be continuing.

Notwithstanding the above, any of our subsidiaries may consolidate with, merge into or transfer all or part of its properties to us. (Section 5.1)

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Events of Default

Unless otherwise specified in the resolutions of our Board, officer’s certificate or supplemental indenture establishing a series of debt securities, “Event of Default” means with respect to any series of debt securities, any of the following:

	●	default in the payment of any interest upon any debt security of that series when it becomes due and payable, and continuance of such default for a period of thirty (30) days (unless the entire amount of the payment is deposited by us with the trustee or with a paying agent prior to the expiration of the thirty (30)-day period);
	●	default in the payment of principal of any security of that series at its maturity;
	●	default in the performance or breach of any other covenant or warranty by us in the indenture (other than a covenant or warranty that has been included in the indenture solely for the benefit of a series of debt securities other than that series), which default continues uncured for a period of sixty (60) days after we receive written notice from the trustee or Windtree and the trustee receive written notice from the holders of not less than 25% in principal amount of the outstanding debt securities of that series as provided in the indenture;
	●	certain voluntary or involuntary events of bankruptcy, insolvency or reorganization of the Company; and
	●	any other Event of Default provided with respect to debt securities of that series that is described in the applicable prospectus supplement. (Section 6.1)

No Event of Default with respect to a particular series of debt securities (except as to certain events of bankruptcy, insolvency or reorganization) necessarily constitutes an Event of Default with respect to any other series of debt securities. (Section 6.1) The occurrence of certain Events of Default or an acceleration under the indenture may constitute an event of default under certain indebtedness of ours or our subsidiaries outstanding from time to time.

We will provide the trustee written notice of any Default or Event of Default within thirty (30) days of becoming aware of the occurrence of such Default or Event of Default, which notice will describe in reasonable detail the status of such Default or Event of Default and what action we are taking or propose to take in respect thereof. (Section 6.1)

If an Event of Default with respect to debt securities of any series at the time outstanding occurs and is continuing, then the trustee or the holders of not less than 25% in principal amount of the outstanding debt securities of that series may, by a notice in writing to us (and to the trustee if given by the holders), declare to be due and payable immediately the principal of (or, if the debt securities of that series are discount securities, that portion of the principal amount as may be specified in the terms of that series) and accrued and unpaid interest, if any, on all debt securities of that series. In the case of an Event of Default resulting from certain events of bankruptcy, insolvency or reorganization, the principal (or such specified amount) of and accrued and unpaid interest, if any, on all outstanding debt securities will become and be immediately due and payable without any declaration or other act on the part of the trustee or any holder of outstanding debt securities. At any time after a declaration of acceleration with respect to debt securities of any series has been made, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of a majority in principal amount of the outstanding debt securities of that series may rescind and annul the acceleration if all Events of Default, other than the non-payment of accelerated principal and interest, if any, with respect to debt securities of that series, have been cured or waived as provided in the indenture. (Section 6.2) We refer you to the prospectus supplement relating to any series of debt securities that are discount securities for the particular provisions relating to acceleration of a portion of the principal amount of such discount securities upon the occurrence of an Event of Default.

The indenture provides that the trustee may refuse to perform any duty or exercise any of its rights or powers under the indenture unless the trustee receives indemnity satisfactory to it against any cost, liability or expense which might be incurred by it in performing such duty or exercising such right or power. (Section 7.1(e)) Subject to certain rights of the trustee, the holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee with respect to the debt securities of that series. (Section 6.12)

No holder of any debt security of any series will have any right to institute any proceeding, judicial or otherwise, with respect to the indenture or for the appointment of a receiver or trustee, or for any remedy under the indenture, unless:

●

that holder has previously given to the trustee written notice of a continuing Event of Default with respect to debt securities of that series; and

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●

the holders of not less than 25% in principal amount of the outstanding debt securities of that series have made written request, and offered indemnity or security satisfactory to the trustee, to the trustee to institute the proceeding as trustee, and the trustee has not received from the holders of not less than a majority in principal amount of the outstanding debt securities of that series a direction inconsistent with that request and has failed to institute the proceeding within sixty (60) days. (Section 6.7)

No holder of debt securities under the indenture may use the indenture to prejudice the rights of another holder or to obtain a preference or priority over another holder of debt securities. (Section 6.7)

Notwithstanding any other provision in the indenture, the holder of any debt security will have an absolute and unconditional right to receive payment of the principal of, premium and any interest on that debt security on or after the due dates expressed in that debt security and to institute suit for the enforcement of payment. (Section 6.8)

The indenture requires us, within one hundred twenty (120) days after the end of our fiscal year, to furnish to the trustee a statement as to compliance with the indenture. (Section 4.3) If a Default or Event of Default occurs and is continuing with respect to the securities of any series and if it is known to a responsible officer of the trustee, the trustee shall mail to each holder of the securities of that series notice of a Default or Event of Default within ninety (90) days after it occurs or, if later, after a responsible officer of the trustee has knowledge of such Default or Event of Default (except if such Default or Event of Default has been validly cured or waived before the trustee gives such notice). The indenture provides that the trustee may withhold notice to the holders of debt securities of any series of any Default or Event of Default (except in payment on any debt securities of that series) with respect to debt securities of that series if the trustee determines in good faith that withholding notice is in the interest of the holders of those debt securities. (Section 7.5)

Modification and Waiver

We and the trustee may modify, amend or supplement the indenture or the debt securities of any series without the consent of any holder of any debt security:

	●	to cure any ambiguity, defect or inconsistency;
	●	to comply with covenants in the indenture described above under the heading “Consolidation, Merger and Sale of Assets”;
	●	to provide for uncertificated securities in addition to or in place of certificated securities;
	●	to add guarantees with respect to debt securities of any series or secure debt securities of any series;
	●	to surrender any of our rights or powers under the indenture;
	●	to add covenants or events of default for the benefit of the holders of debt securities of any series;
	●	to comply with the applicable procedures of the applicable depositary;
	●	to make any change that does not adversely affect the rights of any holder of debt securities;
	●	to provide for the issuance of and establish the form and terms and conditions of debt securities of any series as permitted by the indenture;
	●	to effect the appointment of a successor trustee with respect to the debt securities of any series and to add to or change any of the provisions of the indenture to provide for or facilitate administration by more than one trustee; or
	●	to comply with requirements of the SEC in order to effect or maintain the qualification of the indenture under the Trust Indenture Act. (Section 9.1)

We may also modify and amend the indenture with the written consent of the holders of at least a majority in principal amount of the outstanding debt securities of each series affected by the modifications or amendments. We may not make any modification or amendment without the written consent of the holders of each affected debt security then outstanding if that amendment will:

	●	reduce the amount of debt securities whose holders must consent to an amendment, supplement or waiver;
	●	reduce the rate of or extend the time for payment of interest (including default interest) on any debt security;

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	●	reduce the principal of or premium on or change the fixed maturity of any debt security or reduce the amount of, or postpone the date fixed for, the payment of any sinking fund or analogous obligation with respect to any series of debt securities;
	●	reduce the principal amount of discount securities payable upon acceleration of maturity;
	●	waive a default in the payment of the principal of, premium or interest on any debt security (except a rescission of acceleration of the debt securities of any series by the holders of at least a majority in aggregate principal amount of the then outstanding debt securities of that series and a waiver of the payment default that resulted from such acceleration);
	●	make the principal of or premium or interest on any debt security payable in currency other than that stated in the debt security;
	●	make any change to certain provisions of the indenture relating to, among other things, the right of holders of debt securities to receive payment of the principal of, premium and interest on those debt securities and to institute suit for the enforcement of any such payment and to waivers or amendments; or
	●	waive a redemption payment with respect to any debt security. (Section 9.3)

Except for certain specified provisions, the holders of at least a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all debt securities of that series waive our compliance with provisions of the indenture. (Section 9.2) The holders of a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all the debt securities of such series waive any past default under the indenture with respect to that series and its consequences, except a default in the payment of the principal of, premium or any interest on any debt security of that series; provided, however, that the holders of a majority in principal amount of the outstanding debt securities of any series may rescind an acceleration and its consequences, including any related payment default that resulted from the acceleration. (Section 6.13)

Defeasance of Debt Securities and Certain Covenants in Certain Circumstances

Legal Defeasance. The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, we may be discharged from any and all obligations in respect of the debt securities of any series (subject to certain exceptions). We will be so discharged upon the irrevocable deposit with the trustee, in trust, of money and/or U.S. government obligations or, in the case of debt securities denominated in a single currency other than U.S. Dollars, government obligations of the government that issued or caused to be issued such currency, that, through the payment of interest and principal in accordance with their terms, will provide money or U.S. government obligations in an amount sufficient in the opinion of a nationally recognized firm of independent public accountants or investment bank to pay and discharge each installment of principal, premium and interest on and any mandatory sinking fund payments in respect of the debt securities of that series on the stated maturity of those payments in accordance with the terms of the indenture and those debt securities.

This discharge may occur only if, among other things, we have delivered to the trustee an opinion of counsel stating that we have received from, or there has been published by, the United States Internal Revenue Service a ruling or, since the date of execution of the indenture, there has been a change in the applicable United States federal income tax law, in either case to the effect that, and based thereon such opinion shall confirm that, the holders of the debt securities of that series will not recognize income, gain or loss for United States federal income tax purposes as a result of the deposit, defeasance and discharge and will be subject to United States federal income tax on the same amounts and in the same manner and at the same times as would have been the case if the deposit, defeasance and discharge had not occurred. (Section 8.3)

Defeasance of Certain Covenants. The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, upon compliance with certain conditions:

	●	we may omit to comply with the covenant described under the heading “Consolidation, Merger and Sale of Assets” and certain other covenants set forth in the indenture, as well as any additional covenants which may be set forth in the applicable prospectus supplement; and
	●	any omission to comply with those covenants will not constitute a Default or an Event of Default with respect to the debt securities of that series (“covenant defeasance”).

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The conditions include:

	●	depositing with the trustee money and/or U.S. government obligations or, in the case of debt securities denominated in a single currency other than U.S. Dollars, government obligations of the government that issued or caused to be issued such currency, that, through the payment of interest and principal in accordance with their terms, will provide money in an amount sufficient in the opinion of a nationally recognized firm of independent public accountants or investment bank to pay and discharge each installment of principal of, premium and interest on and any mandatory sinking fund payments in respect of the debt securities of that series on the stated maturity of those payments in accordance with the terms of the indenture and those debt securities; and
	●	delivering to the trustee an opinion of counsel to the effect that we have received from, or there has been published by, the United States Internal Revenue Service a ruling or, since the date of execution of the indenture, there has been a change in the applicable United States federal income tax law, in either case to the effect that, and based thereon such opinion shall confirm that, the beneficial owners of the debt securities of that series will not recognize income, gain or loss for United States federal income tax purposes as a result of the deposit and related covenant defeasance and will be subject to United States federal income tax on the same amounts and in the same manner and at the same times as would have been the case if the deposit and related covenant defeasance had not occurred. (Section 8.4)

No Personal Liability of Directors, Officers, Employees or Stockholders

None of our past, present or future directors, officers, employees or stockholders, as such, will have any liability for any of our obligations under the debt securities or the indenture or for any claim based on, or in respect or by reason of, such obligations or their creation. By accepting a debt security, each holder waives and releases all such liability.

This waiver and release is part of the consideration for the issue of the debt securities. However, this waiver and release may not be effective to waive liabilities under U.S. federal securities laws, and it is the view of the SEC that such a waiver is against public policy. (Section 10.8)

Governing Law

The indenture and the debt securities, including any claim or controversy arising out of or relating to the indenture or the securities, will be governed by the laws of the State of New York.

The indenture will provide that we, the trustee and the holders of the debt securities (by their acceptance of the debt securities) irrevocably waive, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to the indenture, the debt securities or the transactions contemplated thereby.

The indenture will provide that any legal suit, action or proceeding arising out of or based upon the indenture or the transactions contemplated thereby may be instituted in the federal courts of the United States of America located in the City of New York or the courts of the State of New York in each case located in the City of New York, and we, the trustee and the holder of the debt securities (by their acceptance of the debt securities) irrevocably submit to the non-exclusive jurisdiction of such courts in any such suit, action or proceeding. The indenture will further provide that service of any process, summons, notice or document by mail (to the extent allowed under any applicable statute or rule of court) to such party’s address set forth in the indenture will be effective service of process for any suit, action or other proceeding brought in any such court. The indenture will further provide that we, the trustee and the holders of the debt securities (by their acceptance of the debt securities) irrevocably and unconditionally waive any objection to the laying of venue of any suit, action or other proceeding in the courts specified above and irrevocably and unconditionally waive and agree not to plead or claim any such suit, action or other proceeding has been brought in an inconvenient forum. (Section 10.10)

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DESCRIPTION OF WARRANTS

We may issue warrants for the purchase of shares of our common stock or preferred stock or of debt securities. We may issue warrants independently or together with other securities, and the warrants may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and the investors or a warrant agent. The following summary of material provisions of the warrants and warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to a particular series of warrants. The terms of any warrants offered under a prospectus supplement may differ from the terms described below. We urge you to read the applicable prospectus supplement and any related free writing prospectus, as well as the complete warrant agreements and warrant certificates that contain the terms of the warrants.

The particular terms of any issue of warrants will be described in the applicable prospectus supplement. Those terms may include:

	●	the number of shares of common stock or preferred stock purchasable upon the exercise of warrants to purchase such shares and the price at which such number of shares may be purchased upon such exercise;
	●	the designation, stated value and terms (including, without limitation, liquidation, dividend, conversion and voting rights) of the series of preferred stock purchasable upon exercise of warrants to purchase preferred stock;
	●	the principal amount of debt securities that may be purchased upon exercise of a debt warrant and the exercise price for the warrants, which may be payable in cash, securities or other property;
	●	the date, if any, on and after which the warrants and the related debt securities, preferred stock or common stock will be separately transferable;
	●	the terms of any rights to redeem or call the warrants;
	●	the date on which the right to exercise the warrants will commence and the date on which the right will expire;
	●	United States Federal income tax consequences applicable to the warrants; and
	●	any additional terms of the warrants, including terms, procedures, and limitations relating to the exchange, exercise and settlement of the warrants.

Holders of equity warrants will not be entitled to:

	●	vote, consent or receive dividends;
	●	receive notice as stockholders with respect to any meeting of stockholders for the election of our directors or any other matter; or
	●	exercise any rights as stockholders of Windtree.

Each warrant will entitle its holder to purchase the principal amount of debt securities or the number of shares of preferred stock or common stock at the exercise price set forth in, or calculable as set forth in, the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

A holder of warrant certificates may exchange them for new warrant certificates of different denominations, present them for registration of transfer and exercise them at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement. Until any warrants to purchase debt securities are exercised, the holder of the warrants will not have any rights of holders of the debt securities that can be purchased upon exercise, including any rights to receive payments of principal, premium or interest on the underlying debt securities or to enforce covenants in the applicable indenture. Until any warrants to purchase common stock or preferred stock are exercised, the holders of the warrants will not have any rights of holders of the underlying common stock or preferred stock, including any rights to receive dividends or payments upon any liquidation, dissolution or winding up on the common stock or preferred stock, if any.

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Warrant Agent

The warrant agent for any warrants will be set forth in the applicable prospectus supplement.

Description of Outstanding Warrants

See “Description of Our Capital Stock — Common Stock Warrants” for a description of our outstanding warrants.

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DESCRIPTION OF UNITS

We may issue units consisting of any combination of the other types of securities offered under this prospectus in one or more series. We may evidence each series of units by unit certificates that we will issue under a separate agreement. We may enter into unit agreements with a unit agent. Each unit agent will be a bank or trust company that we select. We will indicate the name and address of the unit agent in the applicable prospectus supplement relating to a particular series of units.

The following description, together with the additional information included in any applicable prospectus supplement, summarizes the general features of the units that we may offer under this prospectus. You should read any prospectus supplement and any free writing prospectus that we may authorize to be provided to you related to the series of units being offered, as well as the complete unit agreements that contain the terms of the units. Specific unit agreements will contain additional important terms and provisions and we will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from another report that we file with the SEC, the form of each unit agreement relating to units offered under this prospectus.

If we offer any units, certain terms of that series of units will be described in the applicable prospectus supplement, including, without limitation, the following, as applicable:

	●	the title of the series of units;
	●	identification and description of the separate constituent securities comprising the units;
	●	the price or prices at which the units will be issued;
	●	the date, if any, on and after which the constituent securities comprising the units will be separately transferable;
	●	a discussion of certain United States federal income tax considerations applicable to the units; and
	●	any other terms of the units and their constituent securities.

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DESCRIPTION OF OUR SUBSCRIPTION RIGHTS

As specified in any applicable prospectus supplement, we may issue subscription rights consisting of one or more debt securities, shares of preferred stock, shares of common stock or any combination of such securities.

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GLOBAL SECURITIES

Book-Entry, Delivery and Form

Unless we indicate differently in any applicable prospectus supplement, the securities initially will be issued in book-entry form and represented by one or more global notes or global securities, or, collectively, global securities. The global securities will be deposited with, or on behalf of, The Depository Trust Company, New York, New York, as depositary, or DTC, and registered in the name of Cede & Co., the nominee of DTC. Unless and until it is exchanged for individual certificates evidencing securities under the limited circumstances described below, a global security may not be transferred except as a whole by the depositary to its nominee or by the nominee to the depositary, or by the depositary or its nominee to a successor depositary or to a nominee of the successor depositary.

DTC has advised us that it is:

	●	a limited-purpose trust company organized under the New York Banking Law;
	●	a “banking organization” within the meaning of the New York Banking Law;
	●	a member of the Federal Reserve System;
	●	a “clearing corporation” within the meaning of the New York Uniform Commercial Code; and
	●	a “clearing agency” registered pursuant to the provisions of Section 17A of the Exchange Act.

DTC holds securities that its participants deposit with DTC. DTC also facilitates the settlement among its participants of securities transactions, such as transfers and pledges, in deposited securities through electronic computerized book-entry changes in participants’ accounts, thereby eliminating the need for physical movement of securities certificates. “Direct participants” in DTC include securities brokers and dealers, including underwriters, banks, trust companies, clearing corporations and other organizations. DTC is a wholly-owned subsidiary of The Depository Trust & Clearing Corporation, or DTCC. DTCC is the holding company for DTC, National Securities Clearing Corporation and Fixed Income Clearing Corporation, all of which are registered clearing agencies. DTCC is owned by the users of its regulated subsidiaries. Access to the DTC system is also available to others, which we sometimes refer to as indirect participants, that clear through or maintain a custodial relationship with a direct participant, either directly or indirectly. The rules applicable to DTC and its participants are on file with the SEC.

Purchases of securities under the DTC system must be made by or through direct participants, which will receive a credit for the securities on DTC’s records. The ownership interest of the actual purchaser of a security, which we sometimes refer to as a beneficial owner, is in turn recorded on the direct and indirect participants’ records. Beneficial owners of securities will not receive written confirmation from DTC of their purchases. However, beneficial owners are expected to receive written confirmations providing details of their transactions, as well as periodic statements of their holdings, from the direct or indirect participants through which they purchased securities. Transfers of ownership interests in global securities are to be accomplished by entries made on the books of participants acting on behalf of beneficial owners. Beneficial owners will not receive certificates representing their ownership interests in the global securities, except under the limited circumstances described below.

To facilitate subsequent transfers, all global securities deposited by direct participants with DTC will be registered in the name of DTC’s partnership nominee, Cede & Co., or such other name as may be requested by an authorized representative of DTC. The deposit of securities with DTC and their registration in the name of Cede & Co. or such other nominee will not change the beneficial ownership of the securities. DTC has no knowledge of the actual beneficial owners of the securities. DTC’s records reflect only the identity of the direct participants to whose accounts the securities are credited, which may or may not be the beneficial owners. The participants are responsible for keeping account of their holdings on behalf of their customers.

So long as the securities are in book-entry form, you will receive payments and may transfer securities only through the facilities of the depositary and its direct and indirect participants. We will maintain an office or agency in the location specified in the prospectus supplement for the applicable securities, where notices and demands in respect of the securities and the indenture may be delivered to us and where certificated securities may be surrendered for payment, registration of transfer or exchange.

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Conveyance of notices and other communications by DTC to direct participants, by direct participants to indirect participants and by direct participants and indirect participants to beneficial owners will be governed by arrangements among them, subject to any legal requirements in effect from time to time.

Redemption notices will be sent to DTC. If less than all of the securities of a particular series are being redeemed, DTC’s practice is to determine by lot the amount of the interest of each direct participant in the securities of such series to be redeemed.

Neither DTC nor Cede & Co. (or such other DTC nominee) will consent or vote with respect to the securities. Under its usual procedures, DTC will mail an omnibus proxy to us as soon as possible after the record date. The omnibus proxy assigns the consenting or voting rights of Cede & Co. to those direct participants to whose accounts the securities of such series are credited on the record date, identified in a listing attached to the omnibus proxy.

So long as securities are in book-entry form, we will make payments on those securities to the depositary or its nominee, as the registered owner of such securities, by wire transfer of immediately available funds. If securities are issued in definitive certificated form under the limited circumstances described below and unless if otherwise provided in the description of the applicable securities herein or in the applicable prospectus supplement, we will have the option of making payments by check mailed to the addresses of the persons entitled to payment or by wire transfer to bank accounts in the United States designated in writing to the applicable trustee or other designated party at least fifteen (15) days before the applicable payment date by the persons entitled to payment, unless a shorter period is satisfactory to the applicable trustee or other designated party.

Redemption proceeds, distributions and dividend payments on the securities will be made to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC. DTC’s practice is to credit direct participants’ accounts upon DTC’s receipt of funds and corresponding detail information from us on the payment date in accordance with their respective holdings shown on DTC records. Payments by participants to beneficial owners will be governed by standing instructions and customary practices, as is the case with securities held for the account of customers in bearer form or registered in “street name.” Those payments will be the responsibility of participants and not of DTC or us, subject to any statutory or regulatory requirements in effect from time to time. Payment of redemption proceeds, distributions and dividend payments to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC, is our responsibility, disbursement of payments to direct participants is the responsibility of DTC, and disbursement of payments to the beneficial owners is the responsibility of direct and indirect participants.

Except under the limited circumstances described below, purchasers of securities will not be entitled to have securities registered in their names and will not receive physical delivery of securities. Accordingly, each beneficial owner must rely on the procedures of DTC and its participants to exercise any rights under the securities and the indenture.

The laws of some jurisdictions may require that some purchasers of securities take physical delivery of securities in definitive form. Those laws may impair the ability to transfer or pledge beneficial interests in securities.

DTC may discontinue providing its services as securities depositary with respect to the securities at any time by giving reasonable notice to us. Under such circumstances, in the event that a successor depositary is not obtained, securities certificates are required to be printed and delivered.

As noted above, beneficial owners of a particular series of securities generally will not receive certificates representing their ownership interests in those securities. However, if:

	●	DTC notifies us that it is unwilling or unable to continue as a depositary for the global security or securities representing such series of securities or if DTC ceases to be a clearing agency registered under the Exchange Act at a time when it is required to be registered and a successor depositary is not appointed within ninety (90) days of the notification to us or of our becoming aware of DTC’s ceasing to be so registered, as the case may be;
	●	we determine, in our sole discretion, not to have such securities represented by one or more global securities; or
	●	an Event of Default has occurred and is continuing with respect to such series of securities, we will prepare and deliver certificates for such securities in exchange for beneficial interests in the global securities.

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Any beneficial interest in a global security that is exchangeable under the circumstances described in the preceding sentence will be exchangeable for securities in definitive certificated form registered in the names that the depositary directs. It is expected that these directions will be based upon directions received by the depositary from its participants with respect to ownership of beneficial interests in the global securities.

We have obtained the information in this section and elsewhere in this prospectus concerning DTC and DTC’s book-entry system from sources that are believed to be reliable, but we take no responsibility for the accuracy of this information.

Euroclear and Clearstream

If so provided in the applicable prospectus supplement, you may hold interests in a global security through Clearstream Banking S.A., which we refer to as “Clearstream,” or Euroclear Bank S.A./N.V., as operator of the Euroclear System, which we refer to as “Euroclear,” either directly if you are a participant in Clearstream or Euroclear or indirectly through organizations which are participants in Clearstream or Euroclear. Clearstream and Euroclear will hold interests on behalf of their respective participants through customers’ securities accounts in the names of Clearstream and Euroclear, respectively, on the books of their respective U.S. depositaries, which in turn will hold such interests in customers’ securities accounts in such depositaries’ names on DTC’s books.

Clearstream and Euroclear are securities clearance systems in Europe. Clearstream and Euroclear hold securities for their respective participating organizations and facilitate the clearance and settlement of securities transactions between those participants through electronic book-entry changes in their accounts, thereby eliminating the need for physical movement of certificates.

Payments, deliveries, transfers, exchanges, notices and other matters relating to beneficial interests in global securities owned through Euroclear or Clearstream must comply with the rules and procedures of those systems. Transactions between participants in Euroclear or Clearstream, on one hand, and other participants in DTC, on the other hand, are also subject to DTC’s rules and procedures.

Investors will be able to make and receive through Euroclear and Clearstream payments, deliveries, transfers and other transactions involving any beneficial interests in global securities held through those systems only on days when those systems are open for business. Those systems may not be open for business on days when banks, brokers and other institutions are open for business in the United States.

Cross-market transfers between participants in DTC, on the one hand, and participants in Euroclear or Clearstream, on the other hand, will be effected through DTC in accordance with the DTC’s rules on behalf of Euroclear or Clearstream, as the case may be, by their respective U.S. depositaries; however, such cross-market transactions will require delivery of instructions to Euroclear or Clearstream, as the case may be, by the counterparty in such system in accordance with the rules and procedures and within the established deadlines (European time) of such system. Euroclear or Clearstream, as the case may be, will, if the transaction meets its settlement requirements, deliver instructions to its U.S. depositary to take DTC, and making or receiving payment in accordance with normal procedures for same-day fund settlement. Participants in Euroclear or Clearstream may not deliver instructions directly to their respective U.S. depositaries.

Due to time zone differences, the securities accounts of a participant in Euroclear or Clearstream purchasing an interest in a global security from a direct participant in DTC will be credited, and any such crediting will be reported to the relevant participant in Euroclear or Clearstream, during the securities settlement processing day (which must be a business day for Euroclear or Clearstream) immediately following the settlement date of DTC. Cash received in Euroclear or Clearstream as a result of sales of interests in a global security by or through a participant in Euroclear or Clearstream to a direct participant in DTC will be received with value on the settlement date of DTC but will be available in the relevant Euroclear or Clearstream cash account only as of the business day for Euroclear or Clearstream following DTC’s settlement date.

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Other

The information in this section of this prospectus concerning DTC, Clearstream, Euroclear and their respective book-entry systems has been obtained from sources that we believe to be reliable, but we do not take responsibility for this information. This information has been provided solely as a matter of convenience. The rules and procedures of DTC, Clearstream and Euroclear are solely within the control of those organizations and could change at any time. Neither we nor the trustee nor any agent of ours or of the trustee has any control over those entities and none of us takes any responsibility for their activities. You are urged to contact DTC, Clearstream and Euroclear or their respective participants directly to discuss those matters. In addition, although we expect that DTC, Clearstream and Euroclear will perform the foregoing procedures, none of them is under any obligation to perform or continue to perform such procedures and such procedures may be discontinued at any time. Neither we nor any agent of ours will have any responsibility for the performance or nonperformance by DTC, Clearstream and Euroclear or their respective participants of these or any other rules or procedures governing their respective operations.

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PLAN OF DISTRIBUTION

We may sell the securities from time to time pursuant to underwritten public offerings, “at-the-market offerings,” negotiated transactions, block trades or a combination of these methods or through underwriters or dealers, through agents and/or directly to one or more purchasers. The securities may be distributed from time to time in one or more transactions:

	●	at a fixed price or prices, which may be changed;
	●	at market prices prevailing at the time of sale;
	●	at prices related to such prevailing market prices; or
	●	at negotiated prices.

Each time that we sell securities covered by this prospectus, we will provide a prospectus supplement or supplements that will describe the method of distribution and set forth the terms and conditions of the offering of such securities, including the offering price of the securities and the proceeds to us, if applicable.

Offers to purchase the securities being offered by this prospectus may be solicited directly. Agents may also be designated to solicit offers to purchase the securities from time to time. Any agent involved in the offer or sale of our securities will be identified in a prospectus supplement.

If a dealer is utilized in the sale of the securities being offered by this prospectus, the securities will be sold to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale.

If an underwriter is utilized in the sale of the securities being offered by this prospectus, an underwriting agreement will be executed with the underwriter at the time of sale and the name of any underwriter will be provided in the prospectus supplement that the underwriter will use to make resales of the securities to the public. In connection with the sale of the securities, we or the purchasers of securities for whom the underwriter may act as agent, may compensate the underwriter in the form of underwriting discounts or commissions. The underwriter may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for which they may act as agent. Unless otherwise indicated in a prospectus supplement, an agent will be acting on a best efforts basis and a dealer will purchase securities as a principal, and may then resell the securities at varying prices to be determined by the dealer.

Any compensation paid to underwriters, dealers or agents in connection with the offering of the securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers will be provided in the applicable prospectus supplement. Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters within the meaning of the Securities Act and any discounts and commissions received by them and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions. We may enter into agreements to indemnify underwriters, dealers and agents against civil liabilities, including liabilities under the Securities Act, or to contribute to payments they may be required to make in respect thereof and to reimburse those persons for certain expenses.

The securities issued and sold under this prospectus will have no established trading market, other than our common stock, which is listed on the Nasdaq Capital Market. Any shares of our common stock sold pursuant to this prospectus will be eligible for listing and trading on the Nasdaq Capital Market, subject to official notice of issuance. Any other securities sold pursuant to this prospectus may or may not be listed on a national securities exchange. To facilitate the offering of securities, certain persons participating in the offering may engage in transactions that stabilize, maintain or otherwise affect the price of the securities. This may include over-allotments or short sales of the securities, which involve the sale by persons participating in the offering of more securities than were sold to them. In these circumstances, these persons would cover such over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option, if any. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

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If indicated in the applicable prospectus supplement, underwriters or other persons acting as agents may be authorized to solicit offers by institutions or other suitable purchasers to purchase the securities at the public offering price set forth in the prospectus supplement, pursuant to delayed delivery contracts providing for payment and delivery on the date or dates stated in the prospectus supplement. These purchasers may include, among others, commercial and savings banks, insurance companies, pension funds, investment companies and educational and charitable institutions. Delayed delivery contracts will be subject to the condition that the purchase of the securities covered by the delayed delivery contracts will not at the time of delivery be prohibited under the laws of any jurisdiction in the United States to which the purchaser is subject. The underwriters and agents will not have any responsibility with respect to the validity or performance of these contracts.

We may engage in at-the-market offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement so indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be named in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus and an applicable prospectus supplement. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

The specific terms of any lock-up provisions in respect of any given offering will be described in the applicable prospectus supplement.

The underwriters, dealers and agents may engage in transactions with us, or perform services for us, in the ordinary course of business for which they receive compensation.

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LEGAL MATTERS

Troutman Pepper Hamilton Sanders LLP will pass upon certain legal matters relating to the issuance and sale of the securities offered hereby on behalf of Windtree Therapeutics, Inc. Additional legal matters may be passed upon for us or any underwriters, dealers or agents by counsel that we will name in the applicable prospectus supplement.

EXPERTS

Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, ~~2012, and the effectiveness of our internal control over financial reporting as of December 31, 2012,~~2019, as set forth in their ~~reports~~report, which ~~are~~is incorporated by reference in this prospectus and elsewhere in the registration statement. ~~The report on our~~Our consolidated financial statements for the year ended December 31, 2012 contains an explanatory paragraph describing conditions that raise substantial doubt about the Company's ability to continue as a going concern as described in Note 2 to the consolidated financial statements. Our financial statements are incorporated by reference in reliance on Ernst & Young ~~LLP's reports,~~LLP’s report, given on their authority as experts in accounting and auditing.

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$75,000,000

Common Stock

Preferred Stock

Debt Securities

Warrants

Units

Subscription Rights

____________________________________

PROSPECTUS

, 2020

~~LEG~~AL ~~MATTERS~~

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The information in this prospectus is not complete and ~~when~~may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell nor does it seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

Subject to Completion, dated September 17, 2020

PROSPECTUS

Up to $10,000,000

Common Stock

We have entered into an At The Market Offering Agreement, or the sales agreement, with Ladenburg Thalmann & Co. Inc., or Ladenburg, relating to shares of our common stock offered by this prospectus. In accordance with the ~~validity~~terms of the sales agreement, we may offer and sell shares of our common stock, $0.001 par value per share, or common stock, having an aggregate offering price of up to $10,000,000 from time to time through Ladenburg, acting as sales agent.

Our common stock is listed on the Nasdaq Capital Market under the trading symbol “WINT.” On September 16, 2020, the last reported sale price of our common stock on the Nasdaq Capital Market was $6.79 per share.

Sales of our common stock, if any, under this prospectus may be made in sales deemed to be “at-the-market” equity offerings as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, or the Securities Act, or in privately negotiated transactions. Ladenburg is not required to sell any specific number or dollar amounts of securities, ~~being registered hereunder~~but will act as sales agent and use commercially reasonable efforts to sell on our behalf all of the shares of common stock requested to be sold by us, consistent with its normal trading and sales practices, on mutually agreed terms between Ladenburg and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

Ladenburg will be entitled to compensation at a commission rate of 3.0% of the aggregate gross sales price per share sold. See “Plan of Distribution” beginning on page 14 for additional information regarding Ladenburg’s compensation. In connection with the sale of our common stock on our behalf, Ladenburg may be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of Ladenburg may be deemed to be underwriting commissions or discounts.

Investing in our common stock involves a high degree of risk. Before making an investment decision, please read the information under the heading “Risk Factors” beginning on page 5 of this prospectus and in the documents incorporated by reference into this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.

Ladenburg Thalmann

The date of this prospectus is, 2020

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TABLE OF CONTENTS

ABOUT THIS PROSPECTUS	1

MARKET AND INDUSTRY DATA	2

PROSPECTUS SUMMARY	3

THE OFFERING	4

RISK FACTORS	5

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	7

USE OF PROCEEDS	8

DILUTION	9

DESCRIPTION OF CAPITAL STOCK	10

PLAN OF DISTRIBUTION	14

LEGAL MATTERS	15

EXPERTS	15

WHERE YOU CAN FIND MORE INFORMATION	15

INCORPORATION BY REFERENCE	15

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we have filed with the U.S. Securities and Exchange Commission, or the SEC, utilizing a “shelf” registration process. Under this shelf registration process, we may offer shares of our common stock having an aggregate offering price of up to $10,000,000 from time to time under this prospectus at prices and on terms to be determined by market conditions at the time of offering.

We provide information to you about this offering of shares of our common stock in this prospectus, which describes the specific details regarding this offering. If information in this prospectus is inconsistent with documents incorporated by reference in this prospectus filed prior to the date of this prospectus, you should rely on this prospectus. However, if any statement in one of these documents is inconsistent with a statement in another document having a later date, for example, a document incorporated by reference in this prospectus, the statement in the document having the later date modifies or supersedes the earlier statement as our business, financial condition, results of operations and prospects may have changed since the earlier dates.

You should rely only on the information contained in, or incorporated by reference into, this prospectus and in any free writing prospectus that we may authorize for use in connection with this offering. We have not, and Ladenburg has not, authorized anyone to provide you with any information other than that contained in or incorporated by reference in this prospectus and any free writing prospectus prepared by or on behalf of us or to which we have referred you. We and Ladenburg take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not, and Ladenburg is not, making an offer to sell or soliciting an offer to buy our securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation. You should assume that the information appearing in this prospectus, the documents incorporated by reference into this prospectus, and in any free writing prospectus that we may authorize for use in connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should read this prospectus, the documents incorporated by reference into this prospectus, and any free writing prospectus that we may authorize for use in connection with this offering, in their entirety before making an investment decision. You should also read and consider the information in the documents to which we have referred you in the sections of this prospectus entitled “Where You Can Find More Information” and “Incorporation by Reference.”

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference into this prospectus were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

We are offering to sell, and seeking offers to buy, shares of common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus and the offering of our common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of our common stock and the distribution of this prospectus outside the United States. This prospectus does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

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MARKET AND INDUSTRY DATA

This prospectus, including the information incorporated by reference herein, contains estimates, projections and other information concerning our industry, our business, and the markets for certain drugs, including data regarding the estimated size of those markets, their projected growth rates and the incidence of certain medical conditions. Unless otherwise expressly stated, we obtained the industry, market and competitive position data from our own internal estimates and research, as well as from independent market research, industry, medical and general publications and surveys, governmental agencies and publicly available information in addition to research, surveys and studies conducted by third parties. In some cases, we do not expressly refer to the sources from which this data is derived. In that regard, when we refer to one or more sources of this type of data in any paragraph, you should assume that other data of this type appearing in the same paragraph is derived from the same sources, unless otherwise expressly stated or the context otherwise requires. All market and industry data used involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates.

In addition, while we believe the industry, market and competitive position data included in this prospectus, including the information incorporated by reference herein is reliable and based on reasonable assumptions, such data involve risks and uncertainties and are subject to change based on various factors, including those described in the section titled “Risk Factors,” beginning on page 5 and the “Risk Factors” section included in our Annual Report on Form 10-K for the year ended December 31, 2019 and our Quarterly Reports on Form 10-Q for the quarterly periods ended March 31, 2020 and June 30, 2020, as well as in our subsequent Quarterly Reports on Form 10-Q and our Annual Reports on Form 10-K filed with the SEC. These and other factors could cause results to differ materially from those expressed in the estimates made by the independent parties or by us.

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PROSPECTUS SUMMARY

The following summary highlights information contained or incorporated by reference elsewhere in this prospectus and does not contain all of the information that you should consider in making your investment decision. Before investing in our common stock, you should carefully read this entire prospectus and any related free writing prospectus, as well as the information under the caption “Risk Factors” beginning on page 5 of this prospectus and the “Risk Factors” section included in our Annual Report on Form 10-K for the year ended December 31, 2019 and our QuarterlyReports on Form 10-Q for the quarterly periods ended March 31, 2020 and June 30, 2020, as well as our financialstatements and the related notes thereto in our Annual Report on Form 10-K for the year ended December 31, 2019and our Quarterly Reports on Form 10-Q for the quarterly periods ended March 31, 2020 and June 30, 2020 andany subsequent Quarterly Report on Form 10-Q incorporated by referenceherein.

Company Overview

We are a clinical-stage, biopharmaceutical and medical device company focused on the development of novel therapeutics intended to address significant unmet medical needs in important acute care markets. Our development programs are primarily focused in the treatment of acute cardiovascular and pulmonary diseases. Our lead cardiovascular product candidate istaroxime, a first-in-class, dual-acting agent is being developed to improve cardiac function in patients with acute heart failure, or AHF, and cardiogenic shock with a potentially differentiated safety profile from existing treatments. Istaroxime demonstrated significant improvement in diastolic and systolic function in phase 2 clinical trials and has been granted Fast Track designation for the treatment of AHF by the U.S. Food and Drug Administration, or FDA. Our lead pulmonary product candidate is AEROSURF (lucinactant for inhalation), a novel drug/medical device combination for non-invasive delivery of our proprietary aerosolized KL4 surfactant, using our proprietary aerosol delivery system, or ADS, technology for the treatment of respiratory distress syndrome, or RDS, in premature infants. AEROSURF has been granted Fast Track designation by the FDA for the treatment of RDS. We are also developing plans to conduct a small pilot study of our proprietary KL4 surfactant for the treatment of lung injury resulting from severe novel coronavirus, or COVID-19, infections, if we are able to secure the required regulatory approvals to initiate the study. Our other drug product candidates include rostafuroxin, a novel medicine for the treatment of hypertension in patients with a specific genetic profile. We also have a number of pipeline preclinical product candidates that we are evaluating for progression into clinical development. We are evaluating and pursuing a number of early exploratory research programs to identify potential product candidates, including oral and intravenous SERCA-2a heart failure compounds and other product candidates utilizing our KL4 surfactant and ADS technologies.

Our Development Programs

The table below summarizes the current status and anticipated milestones for our principal product development programs. However, due to the recent global outbreak of COVID-19, our clinical trials and next expected milestones of our product candidates may be impacted, and we may experience delays in anticipated timelines and milestones.

Product Candidate	Indication	Status	Next Expected Milestone
Istaroxime	AHF	Phase 2b	Initiate start-up activities for second phase 2b clinical trial in ~300 patients in second half of 2020.
Istaroxime	Early Cardiogenic Shock	Phase 2a	Initiate phase 2a clinical trial in ~60 patients by end of third quarter 2020.
AEROSURF (aerosolized KL4 surfactant)	RDS	Phase 2b	Initiated in second quarter of 2020 a ~90-patient bridging study with new ADS (developed for use in our phase 3 program), relying on licensee resources.
Rostafuroxin	Genetically Associated Hypertension	Phase 2b	Out-licensing.
Lyophilized KL4 Surfactant	Lung Injury resulting from COVID-19	Pilot	Program planning; targeted IND filing in the third quarter of 2020 and a targeted start date in the second-half of 2020, subject to securing the required regulatory approval to initiate the study.

Corporate Information

We were incorporated in Delaware on November 6, 1992. Our principal executive offices are located at 2600 Kelly Road, Suite 100, Warrington, Pennsylvania 18976, and our telephone number is (215) 488-9300. Our website address is www.windtreetx.com. The information on, or that can be accessed through, our website is not part of this prospectus and is not incorporated by reference herein and you should not consider it part of this prospectus. We have included our website address as an inactive textual reference only.

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THE OFFERING

Common stock offered by us		Shares of our common stock having an aggregate offering price of up to $10,000,000.
Common stock to be outstanding after this offering		Up to 18,341,486 shares of common stock (as more fully described in the notes following this table), assuming sales of 1,472,754 shares of our common stock in this offering at an offering price of $6.79 per share, which was the last reported sale price of our common stock on the Nasdaq Capital Market on September 16, 2020. The actual number of shares issued will vary depending on the sales price under this offering.
Manner of offering		“At-the-market” offering that may be made from time to time through the sales agent, Ladenburg. See “Plan of Distribution” on page 14.
Use of Proceeds		We intend to use the net proceeds from this offering, if any, for working capital and general corporate purposes, which may include capital expenditures, research and development, general and administrative expenses and repayment of indebtedness. See “Use of Proceeds” on page 8.
Risk Factors		An investment in our securities involves a high degree of risk. See “Risk Factors” on page 5 of this prospectus and the other information included in this prospectus and incorporated by reference herein for a discussion of factors you should carefully consider before deciding to invest in our common stock.
Nasdaq Capital Market symbol		“WINT”

The number of shares of our common stock that will be outstanding after this offering is based on 16,868,732 shares of common stock outstanding as of June 30, 2020, and excludes, in each case as of June 30, 2020:

	●	1,761,949 shares of our common stock issuable upon the exercise of stock options outstanding as of June 30, 2020, at a weighted-average exercise price of $17.41 per share;
	●	7,913,900 shares of our common stock issuable upon the exercise of the warrants outstanding as of June 30, 2020, at a weighted-average exercise price of $16.38 per share;
	●	159,556 shares of common stock available for future grant as of June 30, 2020 under our 2011 Long-Term Incentive Plan, as amended; and
	●	35,000 shares of common stock issuable upon the vesting of restricted stock units outstanding as of June 30, 2020.

Unless otherwise stated, all information contained in this prospectus reflects an assumed public offering price of $6.79 per share, which was the last reported sale price of our common stock on the Nasdaq Capital Market on September 16, 2020.

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RISK FACTORS

Investing in our common stock involves a high degree of risk. You should consider carefully the following risks anduncertainties as well as the risks and uncertainties described in the sections entitled “Risk Factors” contained in ourAnnual Report on Form 10-K for the year ended December 31, 2019, as filed with the SEC on April 3, 2020, our Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2020, asfiled with the SEC on May 13, 2020 and our Quarterly Report on Form 10-Q for the quarterlyperiod ended June 30, 2020, as filed with the SEC on August 14, 2020, as updated by our subsequent filings underthe Securities Exchange Act of 1934, as amended, or the Exchange Act, each of which is incorporated in this prospectus by reference in their entirety, together with other information in this prospectus, the information and documents incorporated by reference and any free writing prospectus that we may authorize for use in connection with this offering before you make a decision to invest in our common stock. These risks and uncertainties are not the only risks and uncertainties we face. Additional risks and uncertainties not currently known to us, or that we currently view as immaterial, may also impair our business, operating results, prospects or financial condition. If any of the risks or uncertainties described in our SEC filings or any additional risks and uncertainties actually occur, our business, financial condition, results of operations and prospects could be materially and adversely affected. In that case, the trading price of our common stock could decline and you might lose all or part of your investment.

Risks Related to this Offering

Our management team may invest or spend the proceeds of this offering in ways with which you may not agree or in ways which may not yield a significant return.

Our management will have broad discretion over the use of proceeds from this offering. We intend to use the net proceeds, if any, from this offering for working capital and general corporate purposes, which may include capital expenditures, research and development, general and administrative expenses and repayment of indebtedness. Our management will have considerable discretion in the application of the net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. The net proceeds may be used for corporate purposes that do not increase our operating results or enhance the value of our common stock.

You may experience immediate and substantial dilution in the net tangible book value per share of the common stock you purchase.

The price per share of our common stock being offered may be higher than the net tangible book value per share of our common stock outstanding prior to this offering. Assuming that an aggregate of 1,472,754 shares are sold at an assumed offering price of $6.79 per share, the last reported sale price of our common stock on the Nasdaq Capital Market on September 16, 2020, for aggregate gross proceeds of $10,000,000 in this offering, and after deducting commissions and estimated aggregate offering expenses payable by us, you will suffer immediate and substantial dilution of $6.78 per share, representing the difference between the as adjusted net tangible book value per share of our common stock as of June 30, 2020 after giving effect to this offering and the assumed offering price. To the extent that any options or warrants are exercised, any restricted stock units vest and are settled, any new equity awards are issued under our equity incentive plans, or we otherwise issue additional shares of common stock in the future (including shares issued in connection with strategic and other transactions), you will experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations, even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders. See the section entitled “Dilution” below for a more detailed discussion of the dilution you will incur if you purchase common stock in this offering.

Sales of our common stock in this offering, or the perception that such sales may occur, could cause the market price of our common stock to fall.

We may issue and sell shares of our common stock for aggregate gross proceeds of up to $10,000,000 from time to time in connection with this offering. The actual number of shares of common stock that may be issued and sold in this offering, as well as the timing of any such sales, will depend on a number of factors, including, among others, the prices at which any shares are actually sold in this offering (which may be influenced by market conditions, the trading price of our common stock and other factors) and our determinations as to the appropriate timing, sources and amounts of funding we need. The issuance and sale from time to time of these new shares of common stock, or the mere fact that we are able to issue and sell these shares in this offering, could cause the market price of our common stock to decline.

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You may experience future dilution as a result of future equity offerings.

In order to raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock. We cannot assure you that we will be able to sell shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of our common stock or other securities convertible into or exchangeable for our common stock in future transactions may be higher or lower than the price per share in this offering. As of June 30, 2020, 1,956,505 shares of common stock were either subject to outstanding options or restricted stock unit awards, or reserved for future issuance under our equity incentive plans and are eligible for sale in the public market to the extent permitted by the provisions of various vesting schedules and 7,913,900 shares are reserved for the exercise of warrants outstanding.

It is not possible to predict the aggregate proceeds resulting from sales made under the sales agreement.

Subject to certain limitations in the sales agreement and compliance with applicable law, we have the discretion to deliver a placement notice to the sales agent, Ladenburg, at any time throughout the term of the sales agreement. The number of shares that are sold through Ladenburg after delivering a placement notice will fluctuate based on a number of factors, including the market price of our common stock during the sales period, any limits we may set with Ladenburg in any applicable placement notice and the demand for our common stock. Because the price per share of each share sold pursuant to the sales agreement will fluctuate over time, it is not currently possible to predict the aggregate proceeds to be raised in connection with sales under the sales agreement.

Sales of common stock offered hereby will be in “at-the-market offerings,” and investors who buy shares atdifferent times will likely pay different prices.

Investors who purchase shares in this offering at different times will likely pay different prices, and accordingly may experience different levels of dilution and different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices and number of shares sold in this offering. In addition, subject to the final determination by our board of directors, or the Board, or any restrictions we may place in any applicable placement notice delivered to Ladenburg, there is no minimum or maximum sales price for shares to be sold in this offering. Investors may experience a decline in the value of the shares they purchase in this offering as a result of sales made at prices lower than the prices they paid.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, including the documents that we incorporate by reference herein, and any free writing prospectus that we have authorized for use in connection with this offering, contains forward-looking statements within the meaning of Section 27A of the Securities Act, Section 21E of the Exchange Act and the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical facts contained in this prospectus are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplate,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions, although not all forward-looking statements contain these words. These forward-looking statements include, but are not limited to, statements about:

	●	our estimates regarding future results of operations, financial position, research and development costs, capital requirements and our needs for additional financing;
	●	how long we can continue to fund our operations with our existing cash and cash equivalents;
	●	delays in our anticipated clinical timelines and milestones associated with COVID-19;
	●	the results, cost and timing of our preclinical studies and clinical trials, as well as the number of required trials for regulatory approval and the criteria for success in such trials;
	●	legal and regulatory developments in the U.S. and foreign countries, including any actions or advice that may affect the design, initiation, timing, continuation, progress or outcome of clinical trials or result in the need for additional clinical trials;
	●	the difficulties and expenses associated with obtaining and maintaining regulatory approval of our product candidates, and the indication and labeling under any such approval;
	●	our plans and ability to successfully execute development activities and commercialize our product candidates;
	●	risks related to manufacturing active pharmaceutical ingredients, drug product, medical devices and other materials we need;
	●	the size and growth of the potential markets for our product candidates, the rate and degree of market acceptance of our product candidates and our ability to serve those markets;
	●	the success of competing therapies and products that are or become available;
	●	our ability to limit our exposure under product liability lawsuits;
	●	our ability to obtain and maintain intellectual property protection for our product candidates;
	●	recently enacted and future legislation regarding the healthcare system, including changes to the Patient Protection and Affordable Care Act;
	●	delays, interruptions or failures in the manufacture and supply of our product candidates;
	●	the performance of third parties upon which we depend, including third-party contract research organizations, contract manufacturing organizations, contractor laboratories and independent contractors;
	●	our ability to recruit or retain key scientific, commercial or management personnel or to retain our executive officers; and
	●	our ability to maintain proper functionality and security of our internal computer and information systems and prevent or avoid cyber-attacks, malicious intrusion, breakdown, destruction, loss of data privacy or other significant disruption.

These forward-looking statements are based on management’s current expectations, estimates, forecasts and projections about our business and the industry in which we operate and management’s beliefs and assumptions and are not guarantees of future performance or development and involve known and unknown risks, uncertainties and other factors that are in some cases beyond our control. As a result, any or all of our forward-looking statements in, or incorporated by reference in, this prospectus may turn out to be inaccurate. Factors that may cause actual results to differ materially from current expectations include, among other things, those factors discussed under “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” or otherwise discussed in our Annual Report on Form 10-K for the fiscal year ended December 31, 2019, our Quarterly Reports on Form 10-Q for the quarterly periods ended March 31, 2020 and June 30, 2020, and in our other filings made from time to time with the SEC after the date of this prospectus. Potential investors are urged to consider these factors carefully in evaluating the forward-looking statements. These forward-looking statements speak only as of the date of this prospectus and the documents incorporated by reference herein, and any free writing prospectus, as applicable. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future. You should, however, review the factors and risks we describe in the reports we will file from time to time with the SEC after the date of this prospectus. See “Where You Can Find More Information.”

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USE OF PROCEEDS

We may issue and sell shares of our common stock having aggregate sales proceeds of up to $10,000,000 from time to time. Because there is no minimum offering amount required pursuant to the sales agreement, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. Actual net proceeds will depend on the number of shares we sell and the prices at which such sales occur. There can be no assurance that we will sell any shares under or fully utilize the sales agreement as a source of financing.

We currently intend to use the net proceeds from the sale of the common stock offered by us hereunder, if any, for working capital and general corporate purposes, which may include capital expenditures, research and development, general and administrative expenses and repayment of indebtedness. As of the date of this prospectus, we cannot estimate with certainty the amount of net proceeds to be used for the purposes described above. We may find it necessary or advisable to use the net proceeds for other purposes, and we will have broad discretion in the application of the net proceeds. Pending the uses described above, we plan to invest the net proceeds from this offering in short-term, interest-bearing obligations, investment-grade instruments or other securities.

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DILUTION

If you invest in our common stock, your ownership interest will be diluted to the extent of the difference between the public offering price per share of our common stock and the as adjusted net tangible book value per share of our common stock immediately after the closing of this offering.

Net tangible book value per share represents our total tangible assets less total liabilities, divided by the number of shares of our common stock outstanding. Dilution with respect to net tangible book value per share represents the difference between the amount per share paid by purchasers of shares of common stock in this offering and the net tangible book value per share of our common stock immediately after this offering.

As of June 30, 2020, our historical net tangible book value was $(9.3) million, or $(0.55) per share, based on 16,868,732 shares of common stock outstanding as of June 30, 2020.

After giving effect to the sale of our common stock in the aggregate amount of $10.0 million in this offering at an assumed offering price of $6.79, the last reported sale price of our common stock on the Nasdaq Capital Market on September 16, 2020, and after deducting commissions and estimated aggregate offering expenses payable by us, our as adjusted net tangible book value as of June 30, 2020 would have been approximately $0.2 million, or $0.01 per share. This represents an immediate increase in net tangible book value of $0.56 per share to existing stockholders and immediate dilution in net tangible book value of $6.78 per share to new investors purchasing our common stock in this offering. The following table illustrates this dilution on a per share basis:

Assumed public offering price per share				$	6.79
Net tangible book value per share as of June 30, 2020	$	(0.55	)
Increase per share attributable to new investors	$	0.56
As adjusted net tangible book value per share after this offering				$	0.01
Dilution per share to new investors				$	6.78

The shares sold in this offering, if any, will be sold from time to time at various prices. An increase (decrease) of $1.00 per share in the price at which the shares are sold from the assumed offering price of $6.79 per share shown in the table above, assuming all of our common stock in the aggregate amount of $10.0 million is sold at that price, would cause our as adjusted net tangible book value per share after the offering to be $0.01 per share and would increase (decrease) the dilution in net tangible book value per share to new investors by $1.00 per share, after deducting commissions and estimated aggregate offering expenses payable by us. This information is supplied for illustrative purposes only.

To the extent that outstanding options or warrants are exercised or outstanding restricted stock awards vest, investors purchasing our common stock in this offering will experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

The above discussion and table are based on 16,868,732 shares of common stock outstanding as of June 30, 2020, and excludes, in each case as of June 30, 2020:

	●	1,761,949 shares of our common stock issuable upon the exercise of stock options outstanding as of June 30, 2020, at a weighted-average exercise price of $17.41 per share;
	●	7,913,900 shares of our common stock issuable upon the exercise of the warrants outstanding as of June 30, 2020, at a weighted-average exercise price of $16.38 per share;
	●	159,556 shares of common stock available for future grant as of June 30, 2020 under our 2011 Long-Term Incentive Plan, as amended; and
	●	35,000 shares of common stock issuable upon the vesting of restricted stock units outstanding as of June 30, 2020.

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DESCRIPTION OF CAPITAL STOCK

The following description of our capital stock does not purport to be complete and is subject to, and qualified in its entirety by, our Amended and Restated Certificate of Incorporation, as amended, or the Certificate of Incorporation, and Amended and Restated By-Laws, or the By-Laws, which have been publicly filed with the SEC. See “Where You Can Find More Information.” For a complete description, you should refer to our Certificate of Incorporation and By-Laws, copies of which are incorporated by reference as exhibits to the registration statement of which this prospectus is a part. The terms of our capital stock may also be affected by Delaware law.

General

Our Certificate of Incorporation authorizes 120,000,000 shares of common stock, $0.001 par value per share, and 5,000,000 shares of preferred stock, $0.001 par value per share.

Common Stock

As of September 17, 2020, there were 16,886,482 shares of our common stock issued and outstanding. Subject to any preferential rights of any preferred stock created by Board, holders of our common stock are entitled to such dividends, if any, as our Board may declare from time to time out of funds that we can legally use to pay dividends.

Holders of our common stock are entitled to one vote for each share of common stock and do not have any right to cumulate votes in the election of directors. Upon our liquidation, dissolution or winding-up, holders of our common stock will be entitled to receive on a proportionate basis any assets remaining after provision for payment of creditors and after payment of any liquidation preferences to holders of preferred stock. Holders of our common stock have no preemptive rights and no conversion rights or other subscription rights. There are no redemption or sinking fund provisions applicable to our common stock. All the outstanding shares of common stock are, and the shares offered by this prospectus, when issued and paid for, will be, validly issued, fully paid and nonassessable. The rights and privileges of the holders of our common stock are subject to and may be adversely effected by the rights of the holders of shares of any series of preferred stock that we may issue.

Preferred Stock

Our Board may divide the preferred stock into any number of series, fix the designation and number of shares of each such series, and determine or change the designation, relative rights, preferences and limitations of any series of preferred stock. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions and other corporate purposes, could, among other things, have the effect of delaying, deferring or preventing a change in our control and may adversely affect the market price of the common stock and the voting and other rights of the holders of our common stock.

Common Stock Warrants

May 2020 Warrants

On May 22, 2020, we completed a registered public offering for the purchase of an aggregate of 3,172,413 units consisting of: (i) one share of our common stock and (ii) a warrant to purchase one share of our common stock at an exercise price per share of common stock equal to $7.975, or the May 2020 warrants. As of September 17, 2020, there are 3,154,663 May 2020 warrants currently outstanding. The May 2020 warrants were immediately exercisable upon issuance, in whole or in part, and expire on May 22, 2025. The May 2020 warrants may not be exercised to the extent that, following such exercise, the holder would beneficially own more than 4.99% (or, at the election of the purchaser prior to the date of issuance, 9.99%) of our outstanding shares of common stock, except that upon at least sixty-one (61) days’ prior notice from the holder to us, the holder may increase the amount of ownership of outstanding stock after exercising the holder’s May 2020 warrants up to 9.99% (or up to 19.99% upon prior written approval of the Company) of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the May 2020 warrants. The May 2020 warrants contain customary provisions that adjust the exercise price and the number of shares in the event of a corporate transaction.

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December 2019 Private Placement Warrants

On December 6, 2019, we completed a private placement offering with select institutional investors for the purchase of an aggregate of 2,916,666 shares of common stock and we issued Series I Warrants to purchase up to 1,458,333 shares of our common stock, at an exercise price equal to $12.09 per share, or the Series I Warrant Shares. The Series I Warrants may be exercised on the six-month anniversary of the date of issuance and through the 5-year anniversary of the date of issuance. The Series I Warrants may be exercised for cash or on a cashless basis if there is no effective registration statement registering the resale of the Series I Warrant Shares and may not be exercised to the extent that the holder thereof would, following such exercise or conversion, beneficially own more than 4.99% (or such other percent as designated by each holder not to exceed 19.99%) of our outstanding shares of common stock. The Series I Warrants contain customary provisions that adjust the exercise price and the number of Series I Warrant Shares in the event of a corporate transaction. On May 6, 2020, we entered into an amendment with certain holders of our Series I Warrants pursuant to which the exercise price of the Series I Warrant was amended from $12.09 to $9.67 if the Series I Warrant is exercised, in whole or in part, prior to December 5, 2021.

December 2018 Private Placement Warrants

On December 21, 2018, we completed a private placement offering with select institutional investors for the purchase of an aggregate of 3,928,513 shares of our common stock. In connection with this financing, we issued (i) Series F Warrants to purchase an aggregate of 667,847 shares of common stock, at an exercise price equal to $11.04 per share, which are exercisable through the 18-month anniversary of the date of issuance, or the Series F Warrants, and (ii) Series G Warrants to purchase an aggregate of 1,296,410 shares of common stock, at an exercise price equal to $12.15 per share, which are exercisable through the 5-year anniversary of the date of issuance, or the Series G Warrants and, together with the Series F Warrants, the December 2018 Warrants. The December 2018 Warrants (i) may not be exercised to the extent that, following such exercise, the holder would beneficially own more than 9.99% (or other percent as designated by each holder) of our outstanding shares of common stock, and (ii) otherwise contain customary provisions that adjust the exercise price and the number of shares of common stock into which they may be exercised in the event of a corporate transaction. On April 24, 2020, we entered into an amendment with the holders of our Series F Warrants whereby the expiration date of the Series F Warrant was extended from June 24, 2020 to December 24, 2020.

AEROSURF Warrants (December 2018)

In connection with our acquisition of CVie Investments Limited, an exempted company with limited liability incorporated under the laws of the Cayman Islands, our Board declared a dividend to the holders of record of our outstanding shares of common stock, and holders of certain warrants to purchase common stock, that were outstanding on December 20, 2018 of 0.6148 Series H (AEROSURF) Warrant, for each share of common stock held by a shareholder or each warrant held by a warrant holder, as applicable, on the record date, or the AEROSURF Warrants. The Company expects to distribute AEROSURF Warrants that are exercisable for an aggregate of 987,722 shares of common stock. Each AEROSURF Warrant has a term of five years and provides for automatic exercise into one share of common stock, without any exercise price, upon the Company’s public announcement of the dosing of the first human subject enrolled in the Company’s phase 3 clinical trial for AEROSURF.

Battelle Collaboration Agreement Warrants (October 2014 and December 2018)

We entered into the Battelle Collaboration Agreement with Battelle Memorial Institute, or Battelle, in October 2014, which was amended in August 2015 and March 2016, for the development of a new version of our ADS. In connection with the Battelle Collaboration Agreement, on October 10, 2014, we issued to Battelle warrants to purchase 1,190 shares of common stock, exercisable at a price of $4,200.00 per share, which expire on October 10, 2024. In December 2018, we and Battelle entered into the Battelle Payment Restructuring, which reflected the terms of an October 2017 nonbinding memorandum of understanding, in which we outlined terms to restructure approximately $4.3 million then due to Battelle, under a Research and Development Services Agreement dated as of June 22, 2012 and the Battelle Collaboration Agreement. In connection with the Battelle Payment Restructuring, on December 11, 2018, we issued to Battelle warrants to purchase 25,000 shares of common stock, exercisable at a price of $19.50 per share, which expire on December 7, 2023.

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Panacea Venture Management Company Ltd. Warrants (July 2018)

On July 2, 2018, we issued to Panacea Venture Management Company Ltd., or Panacea, a Secured Convertible Promissory Note, or the Panacea Note, with respect to a loan facility in the aggregate amount of up to $1.5 million, which was funded in two loans of $1.0 million on the date of the Panacea Note and $0.5 million on July 23, 2018. In connection with the Panacea Note, we issued to Panacea warrants, or the Series D Warrants, to purchase 62,500 shares, or the Series D Warrant Shares, at an exercise price of $12.00 per Series D Warrant Share, or the Exercise Price. The Series D Warrants may be exercised at any time beginning six months after the date of issuance and through the fifth anniversary of the date of issuance. The Series D Warrants may not be exercised to the extent that the holder thereof would, following such exercise, beneficially own more than 9.99% (or such other percent as designated by each holder) of the Company’s outstanding shares of common stock, which percentage may be increased, decreased or waived by such holder upon sixty-one (61) days’ notice to us. The Series D Warrants also contain customary provisions that adjust the Exercise Price and the number of Series D Warrant Shares in the event of a corporate transaction.

LPH II Warrants (April 2018)

February 2017 Private Placement Warrants

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July 2015 Warrants

Anti-Takeover Effects of Provisions of the General Corporation Law of the State of Delaware, our Certificate of Incorporation and our By-Laws

Certificate of Incorporation and By-Laws

Section 203 of the DGCL

As a corporation organized under the laws of the State of Delaware, we are subject to Section 203 of the DGCL, which restricts our ability to enter into business combinations with an interested stockholder, the owner of 15% or more of the corporation’s voting stock, or an interested stockholder’s affiliates or associates, for a period of three years after such person became an interested stockholder. These restrictions do not apply if:

●

before becoming an interested stockholder, our Board approves either the business combination or the transaction in which the stockholder becomes an interested stockholder;

●

Choice of Forum

Our Certificate of Incorporation provides that, the Court of Chancery of the State of Delaware will be the sole and exclusive forum for: (i) any derivative action or proceeding brought on behalf of us; (ii) any action asserting a claim of breach of a fiduciary duty owed by any of our directors, officers to us or our stockholders; (iii) any action asserting a claim against us arising pursuant to any provision of the DGCL or Certificate of Incorporation or By-Laws; or (iv) any action asserting a claim against us governed by the internal affairs doctrine. The exclusive forum provision in our Certificate of Incorporation shall not apply to any actions or proceedings brought against us under the Securities Act or Exchange Act, whereby the U.S. District Court for the District of Delaware shall be the sole and exclusive forum.

Limitations of Liability and Indemnification Matters

Listing

Our common stock is listed on the Nasdaq Capital Market under the symbol “WINT.”

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Continental Stock Transfer & Trust Company. The transfer agent and registrar’s address is 1 State Street, 30^th Floor, New York, New York 10004.

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PLAN OF DISTRIBUTION

We have entered into the sales agreement with Ladenburg, under which we may offer and sell up to $10,000,000 of our shares of common stock from time to time through Ladenburg acting as agent and/or principal. Sales of our shares of common stock, if any, under this prospectus will be made by any method that is deemed to be an “at-the-market offering” as defined in Rule 415(a)(4) under the Securities Act or in privately negotiated transactions.

Each time we wish to issue and sell shares of common stock under the sales agreement, we will notify Ladenburg of the number of shares to be issued, the dates on which such sales may be made, any limitation on the number of shares to be sold in any one day and any minimum price below which sales may not be made. Once we have so instructed Ladenburg, unless Ladenburg declines to accept the terms of such notice, Ladenburg has agreed to use its commercially reasonable efforts consistent with its normal trading and sales practices to sell such shares up to the amount specified on such terms. The obligations of Ladenburg under the sales agreement to sell our shares of common stock are subject to a number of conditions that we must meet.

Under the terms of the sales agreement, we may also sell our shares of common stock to the agent as principal for its own account at prices agreed upon at the time of sale. If we sell our shares of common stock to the agent as principal, we will enter into a separate terms agreement with the agent.

The settlement of sales of shares between us and Ladenburg is generally anticipated to occur on the second trading day following the date on which the sale was made, or on some other date that is agreed upon by and between us and Ladenburg in connection with a particular transaction, in return for payment of the net proceeds to us. Sales of our shares of common stock as contemplated in this prospectus will be settled through the facilities of The Depository Trust Company or by such other means as we and Ladenburg may agree upon. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.

We will pay Ladenburg a commission in cash of 3.0% of the aggregate gross proceeds we receive from each sale of our shares of common stock through Ladenburg as our agent. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. In addition, we have agreed to reimburse Ladenburg for the fees and disbursements of its counsel, payable upon execution of the sales agreement, in an amount not to exceed $50,000, in addition to certain ongoing disbursements of its legal counsel up to $3,000 per calendar quarter in connection with quarterly diligence bring downs. We estimate that the total expenses for the offering, excluding any commissions or expense reimbursement payable to Ladenburg under the terms of the sales agreement, will be approximately $210,000. The remaining sale proceeds, after deducting any other transaction fees, will equal our net proceeds from the sale of such shares.

Ladenburg will provide written confirmation to us following the close of trading on the Nasdaq Capital Market on each day on which shares of common stock are sold under the sales agreement. Each confirmation will include the number of shares sold on that day, the aggregate gross proceeds of such sales and the proceeds to us.

In connection with the sale of the shares of common stock on our behalf, Ladenburg will be deemed to be an “underwriter” within the meaning of the Securities Act, and the compensation of Ladenburg will be deemed to be underwriting commissions or discounts. We have agreed to indemnify Ladenburg against certain civil liabilities, including liabilities under the Securities Act. We have also agreed to contribute to payments Ladenburg may be required to make in respect of such liabilities.

The offering of our shares of common stock pursuant to the sales agreement will terminate as permitted therein. We and Ladenburg may each terminate the sales agreement at any time upon five (5) business days’ prior notice.

This summary of the material provisions of the sales agreement does not purport to be a complete statement of its terms and conditions. A copy of the sales agreement is filed as an exhibit to the registration statement of which this prospectus forms a part.

Ladenburg and its affiliates have previously, and may in the future provide, various investment banking, commercial banking, financial advisory and other financial services for us and our affiliates, for which services they have received, and may in the future receive customary fees. In the course of its business, Ladenburg may actively trade our securities for its own account or for the accounts of customers, and, accordingly, Ladenburg may at any time hold long or short positions in such securities.

This prospectus in electronic format may be made available on a website maintained by ~~Dentons US LLP.~~Ladenburg, and Ladenburg may distribute this prospectus electronically.

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LEGAL MATTERS

Troutman Pepper Hamilton Sanders LLP will pass upon certain legal matters relating to this offering. Ellenoff Grossman & Schole LLP, New York, New York has acted as counsel to Ladenburg Thalmann & Co. Inc. in connection with this offering.

EXPERTS

Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2019, as set forth in their report, which is incorporated by reference in this prospectus and elsewhere in the registration statement. Our consolidated financial statements are incorporated by reference in reliance on Ernst & Young LLP’s report, given on their authority as experts in accounting and auditing.

WHERE YOU CAN ~~FIN~~DFIND MORE INFORMATION

We file annual, quarterly and periodic reports, proxy statements and other information with the SEC. You may read and copy any materials that we file with the SEC at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. Many of our SEC filings are also available to the public from the SEC’s Website at “http://www.sec.gov.” We make available free of charge our annual, quarterly and current reports, proxy statements and other information ~~upon request. To request~~with the SEC. The SEC maintains a website that contains reports, proxy and information statements and other information about issuers, such ~~materials, please send an e-mail to ir@DiscoveryLabs.com~~as us, who file electronically with the SEC. The address of that website is http://www.sec.gov.

Our website address is www.windtreetx.com. The information on, or ~~contact John G. Cooper,~~that can be accessed through, our ~~President~~website is not part of this prospectus and Chief Executive Officer, at the following address or telephone number: Discovery Laboratories, Inc., 2600 Kelly Road, Suite 100, Warrington, Pennsylvania 18976, Attention: John G. Cooper; (215) 488-9300. Exhibits to the documents willis not ~~be sent, unless those exhibits have specifically been~~ incorporated by reference inherein and you should not consider it part of this prospectus.

~~We maintain a Website at “http://www.DiscoveryLabs.com”. Our Website and the information contained therein or connected thereto are not incorporated into this Registration Statement.~~

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We have included our website address as an inactive textual reference only.

This prospectus is part of a registration statement that we filed with the SEC ~~a registration statement on Form S-3 under the Securities Act relating to the securities we are offering by this prospectus. This prospectus~~and does not contain all of the information ~~set forth~~ in the registration ~~statement and the exhibits and schedules to the registration~~ statement. ~~Please refer to the~~The full registration statement ~~and its exhibits and schedules for further information with respect to~~may be obtained from the SEC or us, ~~and our securities.~~as provided below. Statements contained in this prospectus asabout other documents are summaries and each statement is qualified in all respects by reference to the ~~contents of any contract or other~~ document ~~are not necessarily complete and, in each instance, we~~to which it refers. You should refer ~~you~~ to the ~~copy of that contract or document filed as an exhibit to the registration statement. You may read and obtain~~actual documents for a ~~copy~~more complete description of the ~~registration statement and its exhibits and schedules from the SEC, as described in the preceding paragraph.~~

~~INFORMATION I~~relevant matters.

~~NCORPORATED~~INCORPORATION BY REFERENCE

The ~~SEC allows~~SEC’s rules allow us to “incorporate by reference” ~~the~~ information ~~we file with them,~~into this prospectus, which means that we can disclose important information to you by referring you to ~~those documents.~~another document filed separately with the SEC. The information incorporated by reference is ~~considered~~deemed to be part of this prospectus, and subsequent information that we file ~~later~~ with the SEC will automatically update and supersede ~~this~~that information. ~~We incorporate by reference the documents filed with SEC listed below:~~

1.	~~Our Annual Report on Form 10-K for the fiscal year ended December 31, 2012, filed on March 14, 2013;~~

Our Current Reports on Form 8-K filed with the SEC on February 2, 2012, February 8, 2012, March 7, 2012, March 16, 2012, March 29, 2012 (excluding the matters in Item 2.02 and Exhibit 99.1 therein, which are not incorporated by reference herein), May 3, 2012 (excluding the matters in Item 2.02 and Exhibit 99.1 therein, which are not incorporated by reference herein), May 10, 2012, May 11, 2012, June 28, 2012, June 29, 2012, August 2, 2012 (excluding the matters in Item 2.02 and Exhibit 99.1 therein, which are not incorporated by reference herein), August 10, 2012, September 18, 2012, September 20, 2012, October 24, 2012, November 8, 2012 (excluding the matters in Item 2.02 and Exhibit 99.1 therein, which are not incorporated by reference herein), January 4, 2013, January 8, 2013, February 13, 2013, February 20, 2013, March 13, 2013 (excluding the matters in Item 2.02 and Exhibit 99.1 therein, which are not incorporated by reference herein), March 15, 2013, April 2, 2013 and April 15, 2013;

3.	~~The description of our common stock contained in our Registration Statement on Form 8-A filed with the SEC on July 13, 1995 and February 6, 2004; and~~

All documents we have filed with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this registration statement and before the effectiveness of the registration statement, as well as after the date of this prospectus and before the termination of this offering, shall be deemed to be incorporated by reference into this prospectus and to be a part of this prospectus from the date of the filing of the documents.

All reports and other documents subsequently filed by us with the SEC pursuant to Sections 13(a), 13(c), 14, or 15(d) of the Securities Exchange Act of 1934 after the date of this prospectus and before the termination of the offering shall be deemed to be incorporated by reference in this prospectus and to be a part of this prospectus from the date of filing of such reports and documents. This prospectus also incorporates by reference any documents that we file with the SEC after the date of the initial registration statement and before the effectiveness of the registration statement. Any statement contained in ~~any~~this prospectus or a previously filed document ~~incorporated or deemed to be~~ incorporated by reference ~~herein shall~~will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus or ~~in any other~~a subsequently filed document ~~which~~incorporated by reference modifies or replaces that statement.

We incorporate by reference our documents listed below and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act between the date of this prospectus and the termination of the offering of the securities described in this prospectus. We are not, however, incorporating by reference any documents or portions thereof, whether specifically listed below or filed in the future, that are not deemed “filed” with the SEC, including any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K.

This prospectus incorporates by reference the documents set forth below that have previously been filed with the SEC:

	●	Our Annual Report on Form 10-K for the year ended December 31, 2019 filed with the SEC on April 3, 2020;
	●	Our Quarterly Report on Form 10-Q for the quarter ended March 31, 2020 and June 30, 2020, filed with the SEC on May 13, 2020 and August 14, 2020;
	●	Our Current Reports on Form 8-K filed with the SEC on March 13, 2020, March 23, 2020, April 24, 2020, April 29, 2020, April 30, 2020, May 7, 2020, May 22, 2020, July 15, 2020 and July 23, 2020; and
	●	The description of our common stock included in our Form 8-A filed with the SEC on May 15, 2020, including any amendments or reports filed for the purpose of updating such description.

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All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also ~~is or is~~be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

You may request a copy, without charge, of any of the documents incorporated by reference in this prospectus ~~modifies~~(other than exhibits, unless they are specifically incorporated by reference in the documents) by writing or ~~supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus.~~

You may request a copy of these filings, at no cost, by sending an e-mail to ir@DiscoveryLabs.com and requesting any one or more of such filings or by contacting John G. Cooper, our Chief Executive Officer,telephoning us at the following ~~address or telephone number: Discovery Laboratories,~~address:

Windtree Therapeutics, Inc.,

2600 Kelly Road, Suite 100

Warrington, Pennsylvania ~~18976-3622,~~ 18976

(215) 488-9300
Attention: ~~John G. Cooper; (215) 488-9300.~~ Chief Financial Officer

Exhibits to the ~~documents~~filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus.

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Up to $10,000,000

Common Stock

PROSPECTUS

Ladenburg Thalmann

You should rely only on the information contained in this prospectus. No dealer, salesperson or other person is authorized to give information that is not contained in this prospectus. This prospectus is not an offer to sell nor is it seeking an offer to buy these securities in any jurisdiction where the offer or sale is not permitted. The information contained in this prospectus is correct only as of the date of this prospectus, regardless of the time of the delivery of this prospectus or any sale of these securities.

The date of this prospectus is, 2020

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and ~~Distribution~~

Distribution.

The following ~~table sets forth all~~is an estimate of the expenses ~~other than the underwriting discounts and commissions, payable~~(all of which are to be paid by the ~~registrant~~registrant) that we may incur in connection with the ~~sale of the~~ securities being ~~registered. All of such fees expenses, except for~~registered hereby, other than the SEC registration ~~fee, are estimates:~~

Amount
Securities and Exchange Commission registration fee $ 712
Accounting fees and expenses $ 10,000
Legal fees and expenses $ 40,000
Transfer agent fees and expenses $ 0
Printing expenses $ 0
Miscellaneous fees and expenses $ 5,000
Total $ 55,712

fee.

SEC registration fee	$	9,735
The Nasdaq Capital Market supplemental listing fee	$	(1	)
Fees and expenses of the trustee	$	(1	)
Printing expenses	$	(1	)
Legal fees and expenses	$	(1	)
Accounting fees and expenses	$	(1	)
Blue Sky, qualification fees and expenses	$	(1	)
Transfer agent fees and expenses	$	(1	)
Miscellaneous	$	(1	)

Total	$	(1	)

(1)	These fees are calculated based on the securities offered and the number of issuances and accordingly cannot be estimated at this time.

Item 15. Indemnification of Directors and ~~Officers~~

Officers.

Article ~~Eighth~~Eight of our ~~Restated~~ Certificate of Incorporation limits the liability of directors to the maximum extent permitted by Delaware law. Delaware law provides that directors of a corporation will not be personally liable for monetary damages for breach of their fiduciary duties as directors, except for liability for (i) any breach of their duty of loyalty to the corporation or its stockholders, (ii) acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law, (iii) unlawful payments of dividends or unlawful stock repurchases or redemptions as provided in Section 174 of the ~~General Corporation Law of the State of Delaware~~DGCL or (iv) any transaction from which the director derives an improper personal benefit.

Our By-Laws provide that we shall indemnify our directors and officers, the directors and officers of any of our subsidiaries and any other individuals acting as directors or officers of any other corporation at our request, to the fullest extent permitted by law.

We have entered into indemnification agreements with ~~certain of~~ our executive officers and directors containing provisions that may require us, among other things, to indemnify them against liabilities that may arise by reason of their status or service as officers or directors, as applicable, other than liabilities arising from willful misconduct of a culpable nature and to advance certain expenses incurred as a result of any proceeding against them as to which they could be indemnified. We have obtained limited directors’ and officers’ liability insurance.

These provisions in our ~~Restated~~ Certificate of Incorporation and our By-Laws do not eliminate the officers’ and directors’ fiduciary duty, and in appropriate circumstances, equitable remedies such as injunctive or other forms of non-monetary relief will remain available under Delaware law. In addition, each officer and director will continue to be subject to liability for breach of their duty of loyalty to us for acts or omissions not in good faith or involving intentional misconduct, for knowing violations of law, for actions leading to improper personal benefit to the officer or director and for payment of dividends or approval of stock repurchases or redemptions that are unlawful under Delaware law. The provisions also do not affect an officer’s or director’s responsibilities under any other law, such as the federal securities laws or state or federal environmental laws.

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* To be filed by amendment or incorporated by reference in connection with the offering of the securities.

‡ To be filed in accordance with the requirements of Item 601(b)(25) of Regulation S-K.

Large accelerated filero	☐	Accelerated filerx	☐
Non-accelerated filero ~~(Do not check if a smaller reporting company)~~	☒	Smaller reporting companyx	☒
		Emerging growth company	☐

Title of Each Class of Securities to be Registered		Amount to be Registered(1)				Proposed Maximum Offering Price per Share(2)				Proposed Maximum Aggregate Offering Price(2)				Amount of Registration Fee(1)(2)
Common Stock, par value $.001 per share			2,340,000			$	2.23			$	5,218,200			$	712

Name	Total Number of Shares of Common Stock Beneficially Owned (1)(2)		Number of Shares Being Offered (1)(2)		Number of Shares to be Beneficially Owned after the Offering		Percentage to be Beneficially Owned after the Offering

Deerfield Private Design Fund II, L.P.		926,874		926,874		0		--
Deerfield Private Design International II, L.P.		1,062,126		1,062,126		0		--
Deerfield Special Situations Fund, L.P.		307,200		205,335		101,865		*
Deerfield Special Situations International Master Fund, L.P.		308,880		145,665		163,215		*

Exhibit ~~No.~~ Number	Exhibit Description
1.1*	~~Method~~ Form of ~~Filing~~Underwriting Agreement.
1.2	At The Market Offering Agreement (filed herewith).
3.1
~~3.1~~	Amended and Restated Certificate of Incorporation of Discovery Laboratories, Inc. (Discovery), as amended by a Certificate of Amendment to the Restated Certificate of Incorporation of Discovery filed on December 27, 2010, as further amended by a Certificate of Amendment to the Restated Certificate of Incorporation of Discovery filed on October 3, 2011.	~~Incorporated~~(incorporated by reference to Exhibit 3.1 to ~~Discovery's Quarterly~~Windtree’s Annual Report ~~for the quarter ended September 30, 2011,~~on Form 10-K, as filed with the SEC on ~~November 14, 2011.~~April 17, 2018).
3.2
~~3.2~~	Certificate of Amendment to the Amended and Restated ~~By-Laws~~Certificate of ~~Discovery, as amended effective September 3, 2009.~~	~~Incorporated~~Incorporation (incorporated by reference to Exhibit 3.1 to ~~Discovery’s Current Report on~~Windtree’s Form 8-K as filed ~~with the SEC~~ on ~~September 4, 2009.~~April 29, 2020).
3.3
~~4.1~~	~~Shareholder Rights Agreement, dated as of February 6, 2004, by~~ Amended and ~~between Discovery and Continental Stock Transfer & Trust Company.~~	~~Incorporated~~Restated By-Laws (incorporated by reference to Exhibit ~~10.1~~3.2 to ~~Discovery’s Current Report on~~Windtree’s Form 8-K as filed ~~with the SEC~~ on ~~February 6, 2004.~~April 18, 2016).
4.1*	Form of Preferred Stock Certificate.
4.2*
~~4.2~~	Certificate of Designations ~~Preferences and Rights~~ of ~~Series A Junior Participating Cumulative~~ Preferred ~~Stock of Discovery, dated February 6, 2004.~~Stock.
4.3	~~Incorporated by reference to Exhibit 2.2 to Discovery’s~~ Form ~~8-A12G, as filed with the SEC on February 6, 2004.~~of Indenture (filed herewith).
4.4*	Form of Debt Security.
4.5*	Form of Warrant.
4.3* 4.6*	Form of Warrant ~~issued to Deerfield Entities (as defined herein).~~Agreement for Common Stock, including Warrant Certificate for Common Stock.
4.7*	~~Incorporated by reference to Exhibit 4.1 to Discovery’s Current Report on~~ Form ~~8-K/A, as filed with the SEC on March 15, 2013.~~of Warrant Agreement for Preferred Stock, including Warrant Certificate for Preferred Stock.
4.8*	Form of Warrant Agreement for Debt Securities, including Warrant Certificate for Debt Securities.
4.9*	Form of Unit.
~~5.1~~ 4.10*	~~Opinion~~ Form of ~~Dentons US LLP, legal counsel.~~Unit Agreement.
4.11*	~~Filed herewith.~~ Form of Subscription Rights Agreement.
5.1	Opinion of Troutman Pepper Hamilton Sanders LLP (filed herewith).
23.1
10.1*	Facility Agreement dated as of February 13, 2013, between Discovery and Deerfield Private Design Fund II, L.P., Deerfield Private Design International II, L.P., Deerfield Special Situations Fund, L.P. and Deerfield Special Situations International Master Fund, L.P. as lenders (the “Deerfield Entities”).	~~Incorporated by reference to Exhibit 10.2 to Discovery’s Current Report on Form 8-K/A, as filed with the SEC on March 15, 2013.~~

~~10.2~~	~~Registration Rights Agreement dated as of February 13, 2013, between Discovery and the Deerfield Entities~~	~~Incorporated by reference to Exhibit 10.2 to Discovery’s Current Report on Form 8-K/A, as filed with the SEC on March 15, 2013.~~

~~10.3~~	~~Security Agreement dated as of February 13, 2013, between Discovery and the Deerfield Entities~~	~~Incorporated by reference to Exhibit 10.3 to Discovery’s Current Report on Form 8-K/A, as filed with the SEC on March 15, 2013.~~

~~23.1~~	Consent of Ernst & Young LLP, ~~independent registered public accounting firm.~~Independent Registered Public Accounting Firm (filed herewith).
23.2	~~Filed herewith.~~ Consent of Troutman Pepper Hamilton Sanders LLP (included in Exhibit 5.1).
24.1
~~23.2~~	~~Consent of Dentons US LLP, legal counsel (included in its opinion filed as Exhibit 5.1 to this registration statement).~~	~~Filed herewith.~~

~~24.1~~	Powers of Attorney ~~(included in~~(incorporated by reference to the signature page ~~to this registration statement)~~hereto).
25.1‡	~~Filed~~ Statement of Eligibility on Form T-1 under the Trust Indenture Act of 1939, as amended, of the trustee, as trustee under the indenture filed herewith.

	~~DISCOVERY LABORATORIES, INC.~~ Windtree Therapeutics, Inc.

	By:	/s/ ~~John G. Cooper~~Craig E. Fraser
	Name:	~~John G. Cooper~~ Craig E. Fraser
	Title:	President and Chief Executive Officer

	~~2600 Kelly Road, Suite 100~~	No.)
	~~Warrington, Pennsylvania 18976-3622~~

~~(1)~~ Title of each class of securities to be registered	~~Includes~~ Amount to be registered/proposed maximum offering price per unit/proposed maximum aggregate offering price	Amount of registration fee
Common Stock, par value $0.001 par value per share	(1)
Preferred Stock, par value $0.001 par value per share	(1)
Debt Securities	(1)
Warrants	(1)
Units	(1)
Subscription Rights	(1)
Total	75,000,000 (2)	9,735 (3)

	●	a base prospectus which covers the offering, issuance and sale by the registrant of up to a maximum aggregate offering price of $75,000,000 of the registrant’s common stock, preferred stock, debt securities, warrants, units and/or subscription rights; and

	●	a prospectus relating to an At The Market Offering Agreement, or the sales agreement, with Ladenburg Thalmann & Co. Inc., covering the offering, issuance and sale by the registrant of up to a maximum aggregate offering price of $10,000,000 of the registrant’s common stock that may be issued and sold from time to time under the sales agreement.

ABOUT THIS PROSPECTUS	3 1

~~PROSPECTUS SUMMARY~~	4

~~FINANCING WITH THE DEERFIELD ENTITIES~~	6

~~RISK FACTORS~~	8

~~FORWARD-LOOKING STATEMENTS~~	10

~~USE OF PROCEEDS~~	12

~~SELLING STOCKHOLDERS~~	12

~~PLAN OF DISTRIBUTION~~	14

~~DESCRIPTION OF COMMON STOCK~~	16

~~EXPERTS~~	18

~~LEGAL MATTERS~~	18

WHERE YOU CAN FIND MORE INFORMATION	18 2

INCORPORATION BY REFERENCE	2

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	4

~~INFORMATION INCORPORATED BY REFERENCE~~ABOUT WINDTREE THERAPEUTICS, INC.	5

RISK FACTORS	6

USE OF PROCEEDS	7

DESCRIPTION OF CAPITAL STOCK	8

DESCRIPTION OF DEBT SECURITIES	12

DESCRIPTION OF WARRANTS	19

DESCRIPTION OF UNITS	21

DESCRIPTION OF OUR SUBSCRIPTION RIGHTS	22

GLOBAL SECURITIES	23

PLAN OF DISTRIBUTION	27

LEGAL MATTERS	29

EXPERTS	29

	Amount
Securities and Exchange Commission registration fee	$	712
Accounting fees and expenses	$	10,000
Legal fees and expenses	$	40,000
Transfer agent fees and expenses	$	0
Printing expenses	$	0
Miscellaneous fees and expenses	$	5,000
Total	$	55,712

Signature	~~Name &~~ Title		Date
/s/ Craig E. Fraser	Director, President, and Chief Executive Officer		September 17, 2020
Craig E. Fraser	(Principal Executive Officer)
/s/ John ~~G. Cooper~~P. Hamill	~~John G. Cooper~~ Senior Vice President and Chief Financial Officer		~~April 15, 2013~~ September 17, 2020
John P. Hamill	~~President, Chief Executive Officer~~(Principal Financial and ~~Director~~
	Accounting Officer)
/s/ ~~John Tattory~~James Huang	~~John Tattory~~		~~April 15, 2013~~
	~~Vice President, Finance, and Chief Accounting Officer~~	September 17, 2020
James Huang	Director (Chairman of the Board)
/s/ Daniel E. Geffken			September 17, 2020
Daniel E. Geffken	Director
/s/ John R. Leone			September 17, 2020
John R. Leone	~~April 15, 2013~~
	~~Chairman of the Board of Directors~~
	Director
/s/ Joseph M. Mahady			September 17, 2020
Joseph M. Mahady	~~April 15, 2013~~
	Director

/s/ Bruce A. Peacock			September 17, 2020
Bruce A. Peacock	~~April 15, 2013~~
	Director
/s/ Brian D. Schreiber, M.D.			September 17, 2020
~~/s/ Marvin E. Rosenthale~~	~~Marvin E. Rosenthale, Ph.D.~~		~~April 15, 2013~~
Brian D. Schreiber, M.D.	Director