As filed with the Securities and Exchange Commission on June 25, 2021September 7, 2022

Registration No. 333-          

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

DELCATH SYSTEMS, INC.

(Exact Name Of Registrant As Specified In Its Charter)

1633 Broadway, Suite 22C

New York, New York 10019

(212) 489-2100

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Gerard Michel

Chief Executive Officer

Delcath Systems, Inc.

1633 Broadway, Suite 22C

New York, New York 10019

(212) 489-2100

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copy to:

Veronica Montagna,Ryan S. Sansom, Esq.

McCarter & English,Nicolas H.R. Dumont

Cooley LLP

100 Mulberry500 Boylston Street Four Gateway Center

Newark, New Jersey 07102Boston, Massachusetts 02116

(973)(617) 639-7948937-2300

Approximate date of commencement of proposed sale to the public:public: From time to time or at one time after the effective date of this registration statement as determined by the Registration Statement as the registrant shall determine.selling securityholders.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  ☐

CALCULATION OF REGISTRATION FEE

The registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. WeThese securities may not sell these securitiesbe sold until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities, and we are not soliciting offers to buy these securities, in any state or other jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, PRELIMINARY PROSPECTUS DATED JUNE 25, 2021SEPTEMBER 7, 2022

PROSPECTUS

$100,000,000

Up to 1,257,705 Shares of Common Stock

Preferred Stock

Senior Debt Securities

Warrants

Units Offered by the Selling Stockholders

We mayThis prospectus relates to the offer and resale, from time to time, issue,by the selling stockholders named under the heading “Selling Stockholders” in onethis prospectus, or more series or classes,their assigns (the “Selling Stockholders”), of up to $100 million in aggregate principal amount1,257,705 shares of our common stock, preferred stock, debt securities, warrants and/or units in one or more offerings. We may offer these securities separately orthe Company’s Common Stock, par value $0.01 per share (the “Common Stock”), which consist of (i) 690,954 shares (the “Shares”) of Common Stock held by the Selling Stockholders and (ii) 566,751 shares of Common Stock (the “Warrant Shares” and together in units, and we may offer securities as may bewith the Shares, the “Securities”) issuable upon conversion, redemption, repurchase, exchange orthe exercise of pre-funded warrants (the “Warrants”) held by the Selling Stockholders. We are registering the offer and sale of the Common Stock held by the Selling Stockholders to satisfy the registration rights they were granted pursuant to a registration rights agreement entered into on July 18, 2022 in connection with the securities purchase agreement as of even date thereof. While we will not receive any proceeds from the sale of the Common Stock by the Selling Stockholders, we will receive proceeds from the exercise of any Warrants for cash.

Our registration of shares of Common Stock covered by this prospectus does not mean that the Selling Stockholders will offer or sell any such shares. The Selling Stockholders may sell shares of Common Stock covered by this prospectus in a number of different ways and at varying prices. For additional information on the possible methods of sale that may be used by the Selling Stockholders, you should refer to the section of this prospectus entitled “Plan of Distribution.” The Selling Stockholders may, individually but not severally, be deemed to be an “underwriter” within the meaning of the securities registered hereunder, including any applicable anti-dilution provisions.

This prospectus provides a general descriptionSecurities Act of 1933, as amended (the “Securities Act”), of the securities we may offer. Each time we offer securities, weshares of Common Stock that they are offering pursuant to this prospectus. The Selling Stockholders will specify in the accompanying prospectus supplement the termsbear all commissions and discounts, if any, attributable to their respective sales of the securities being offered.Common Stock hereunder. We may also authorize one or more free writing prospectuses to be provided to youwill bear all costs, expenses and fees in connection with these offerings. Thethe registration of the Common Stock. We will not be paying any underwriting discounts or commissions in this offering.

A prospectus supplement and any free writing prospectus may also add, update, or change information contained in this prospectus. You should carefully read this prospectus, theany applicable prospectus supplement, and any related free writing prospectus, as well as any documentsthe information incorporated by reference in this prospectus and any applicable prospectus supplement before you invest in our securities.

We may sell these securities to or through underwriters and also to other purchasers or through agents. We will set forth the names of any underwriters or agents, and any fees, conversions or discount arrangements, in an accompanying prospectus supplement. We may not sell any securities under this prospectus without delivery of the applicable prospectus supplement.make your investment decision.

Our common stockCommon Stock is traded on The NASDAQ Capital Market under the symbol “DCTH.” On June 24, 2021,September 6, 2022, the closing price for our common stock,Common Stock, as reported on The NASDAQ Capital Market, was $11.04$4.21 per share. Our principal executive offices are located at 1633 Broadway, Suite 22C, New York, New York 10019.

Investing in ourthese securities involves a high degree of risk. You should review carefully the risks and uncertainties referenced under the headingcertain risks. See “Risk Factors” containedon page 5 of this prospectus. See also “Risk Factors” in the documents incorporated by reference in this prospectus beginning on page 5 and any applicable prospectus supplement, and under similar headings infor a discussion of the other documents that are incorporated by reference into this prospectus.factors you should carefully consider before deciding to purchase these securities.

Neither the Securities and Exchange CommissionSEC nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is                 , 2021.

2022

TABLE OF CONTENTS

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RISK FACTORS

Investing in shares of our Common Stock involves a high degree of risk. Before making an investment decision,deciding whether to invest in shares of our Common Stock, you should consider carefully consider the risks described under “Risk Factors” in the applicable prospectus supplement, together with all of the other information appearingand uncertainties discussed in this prospectus or incorporated by reference into this prospectussection and any applicable prospectus supplement, in light of your particular investment objectives and financial circumstances. Our business, financial condition or results of operations could be materially adversely affected by any of these risks. The trading price of our securities could decline due to any of these risks, and you may lose all or part of your investment. This prospectus and the incorporated documents also contain forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks mentioned elsewhere in this prospectus. You should also consider the risks, uncertainties and assumptions discussed under the heading “Risk Factors” includedsections titled Risk Factors contained in our most recent Annual Report on Form 10-K and which isin our most recent Quarterly Report on fileForm 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, and iswhich are incorporated herein by reference into this prospectus in their entirety, together with other information in this prospectus, the documents incorporated by reference, any prospectus supplement and any free writing prospectus that we may authorize. Please also read carefully the section titled “Cautionary Note Regarding Forward-Looking Statements.”

The market price of our Common Stock has been, and may continue to be volatile and fluctuate significantly, which could result in substantial losses for investors.

The trading price of our Common Stock has been, and we expect it to continue to be, volatile. The price at which our Common Stock trades depends upon a number of factors, including historical and anticipated operating results, our financial situation, announcements of technological innovations or new products by us or our competitors, our ability or inability to raise the additional capital needed and the terms on which it may be amended, supplementedraised, and general market and economic conditions. Some of these factors are beyond our control. Broad market fluctuations may lower the market price of our Common Stock and affect the volume of trading, regardless of our financial condition, results of operations, business or supersededprospects. Among the factors that may cause the market price of our Common Stock to fluctuate are the risks described elsewhere in this “Risk Factors” section and other factors, including:

In addition, the stock markets and the market for pharmaceutical companies in particular, may experience a loss of investor confidence. Such loss of investor confidence may result in extreme price and volume fluctuations in our Common Stock that are unrelated or disproportionate to the operating performance of our business, financial condition or results of operations. These broad market and industry factors may materially harm the market price of our Common Stock and expose the Company to securities class action litigation. Such litigation, even if unsuccessful, could be costly to defend and divert management’s attention and resources, which could further materially harm our financial condition and results of operations.

Sales of a substantial number of shares of our Common Stock in the future.public market, or the perception that such sales may occur, could adversely affect the market price of our Common Stock and could impair our ability to raise additional equity capital.

Sales of a substantial number of shares of our Common Stock in the public market, or the perception that such sales may occur, could cause the market price of our Common Stock to decline and could impair our ability to raise capital through the sale of additional equity securities. We cannot predict the effect that future sales of shares of our Common Stock or other equity-related securities would have on the market price of our Common Stock.

We have a history of reverse splits, which have severely impacted our Common Stock price.

Since our initial public offering in 2000, we have effected five reverse stock splits, for a cumulative ratio since our initial public offering of 1:31,360,000,000. Each such reverse split has resulted in an effective decline in the price of our Common Stock. There can be no assurance that we will not be required to effect one or more additional reverse stock splits which could further impact the market price and liquidity of our Common Stock.

Anti-takeover provisions in our Amended and Restated Certificate of Incorporation and By-laws may reduce the likelihood of a potential change of control or make it more difficult for our stockholders to replace management.

Certain provisions of our Amended and Restated Certificate of Incorporation and By-laws could have the effect of making it more difficult for our stockholders to replace management at a time when a substantial number of stockholders might favor a change in management. These provisions include:

, our board of directors has the authority to issue up to 10,000,000 shares of preferred stock in one or more series and to determine the rights and preferences of the shares of any such series without stockholder approval. Any series of preferred stock is likely to be senior to the Common Stock with respect to dividends, liquidation rights and, possibly, voting rights. The board’s ability to issue preferred stock may have the effect of discouraging unsolicited acquisition proposals, thus adversely affecting the market price of our Common Stock.

We have never declared or paid any dividends to the holders of our Common Stock and we do not expect to pay cash dividends in the foreseeable future.

We intend to retain all earnings for use in connection with the expansion of our business and for general corporate purposes. The board of directors will have the sole discretion in determining whether to declare and pay dividends in the future. The declaration of dividends will depend on profitability, financial condition, cash requirements, future prospects and other factors deemed relevant by our board of directors. Our ability to pay cash dividends in the future could be limited or prohibited by the terms of financing agreements that we may enter into or by the terms of any preferred stock that may be authorized and issued. We do not expect to pay dividends in the foreseeable future. As a result, holders of our Common Stock must rely on stock appreciation for any return on their investment.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, contains forward-looking statementsand the documents incorporated by reference herein, contain, or will contain, “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements can be identified by words such as “intends,” “believes,” “anticipates,” “indicates,” “plans,” “expects,” “suggests,” “may,” “would,” “should,” “potential,” “designed to,” “will,” “ongoing,” “estimate,” “forecast,” “predict,” “could,” and similar references, although not all forward-looking statements contain these words. Forward-looking statements are neither historical facts nor assurances of future performance. These statements are based only on our current beliefs, expectations and assumptions regarding the future of our business, future plans and strategies, projections, anticipated events and trends, the economy and other future conditions. Because forward-looking statements relate to the future, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict and many of which are outside of our control. Risks that could cause actual results to vary from expected results expressed in our forward-looking statements include, but are not limited to:

Our actual results

Forward-looking statements contained in this prospectus speak only as of the date hereofthe statements are made. Except as required under the federal securities laws and rules and regulations of the Company does notSEC, we undertake no obligation to update any of theseor revise forward-looking statements to reflect a changeactual results, changes in its viewsassumptions or events or circumstances that occur afterchanges in other factors affecting forward-looking information. We caution you not to unduly rely on the date of this report.

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forward-looking statements when evaluating the information presented herein.

DESCRIPTIONUSE OF SECURITIESPROCEEDS

We will not receive any of the proceeds from the shares of Common Stock sold by the Selling Stockholders hereunder.

We may offerreceive proceeds from the exercise of the Warrants to the extent the Warrants are exercised. We can make no assurances that any of the Warrants will be exercised, or if exercised, the quantity that will be exercised or the period in which such Warrants will be exercised.

We intend to use the net proceeds from any exercise of the Warrants for working capital and general corporate purposes.

SELLING STOCKHOLDERS

The Common Stock being offered by the Selling Stockholders are those previously issued to the Selling Stockholders, and those issuable to the Selling Stockholders, upon exercise of the Warrants. For additional information regarding the issuances of those shares of Common Stock and warrants, see “Summary—Private Placement” above. We are registering the Common Stock in order to permit the Selling Stockholders to offer the shares for resale from time to time.

The table below lists the Selling Stockholders and other information regarding the beneficial ownership of the Common Stock by each of the Selling Stockholders. The second column lists the number of Common Stock beneficially owned by each selling stockholder, based on its ownership of the Common Stock and the Warrants, as of July 31, 2022, assuming exercise of the Warrants held by the Selling Stockholders on that date, without regard to any limitations on exercises.

The third column lists the Common Stock being offered by this prospectus by the Selling Stockholders.

In accordance with the terms of a registration rights agreement with the Selling Stockholders, this prospectus generally covers the resale of the sum of (i) the number of Common Stock issued to the Selling Stockholders in the Private Placement and (ii) all shares of Common Stock issuable upon exercise of the Warrants issued in the Private Placement.The fourth column assumes the sale of all of the shares offered by the Selling Stockholders pursuant to this prospectus.

In accordance with the terms of a registration rights agreement with the Selling Stockholders, we are required to use commercially reasonable efforts to keep this registration statement continuously effective under the Securities Act until the date that all the registrable securities covered by this registration statement (i) have been sold, hereunder or pursuant to Rule 144, or (ii) may be sold without volume or manner-of-sale restrictions pursuant to Rule 144 and without the requirement for us to be in compliance with the current public information requirement under Rule 144.

Under the terms of the Warrants, a selling stockholder may not exercise the Warrants to the extent such exercise would cause such selling stockholder, together with its affiliates and attribution parties, to beneficially own a number of Common Stock which would exceed 9.99% of our common stockthen outstanding Common Stock following such exercise, excluding for purposes of such determination Common Stock issuable upon exercise of the Warrants which have not been exercised. The number of shares in the second column does not reflect this limitation. The Selling Stockholders may sell all, some or none of their shares in this offering. See “Plan of Distribution.”

SELLING STOCKHOLDER TABLE

Relationship with Selling Stockholders

On April 8, 2020, we entered into a Board Appointment Agreement, dated as of April 8, 2020, with Rosalind Opportunities Fund I L.P. and preferred stock, various seriesRosalind Maser Fund L.P. (“Rosalind”), pursuant to which Steven Salamon and Gil Aharon, who are principals of debtRosalind, have been appointed as directors of the Company’s board of Directors. Certain shares of Common Stock registered for resale hereunder are also held by Gerard Michel, who is the Chief Executive Officer of the Company. Mitchell Robbins, Bigger Capital Fund, LP and District 2 Capital Fund LP have not held any position or office with us or any of our predecessors or affiliates within the last three years and have not had a material relationship with us or any of our predecessors or affiliates within the past three years.

PLAN OF DISTRIBUTION

Each Selling Stockholder, or the Selling Stockholders, of the securities warrants, and units to purchase any such securities with a total value of up to $100,000,000their pledgees, assignees and successors-in-interest may, from time to time, under this prospectus at prices and on terms to be determined by market conditions at the timesell any or all of the offering. Each time we offer a type or series oftheir securities we will provide a prospectus supplement that will describe the specific amounts, prices and other important terms of the securities.

Authorized Capital Stock

The following is a description of the material terms of our capital stock included in our Amended and Restated Certificate of Incorporation, as amended (our “Certificate of Incorporation”), and our Amended and Restated By-Laws (our “By-Laws”). This description of our capital stock does not purport to be complete and is subject to, and qualified in its entirety by, our Certificate of Incorporation and By-Laws, which are exhibits to the registration statement of which this prospectus forms a part, and by applicable law. The terms of our common stock and preferred stock may also be affected by Delaware law.

Our authorized capital stock consists of:

Our common stock is the only class or series of our securities which has been registered under Section 12 of the Securities Exchange Act of 1934, as amended, and is listed on The Nasdaq Capital Market under the symbol “DCTH”. Of the 10,000,000 authorized shares of preferred stock, an aggregate of 52,960 shares are designated as Series E Preferred Stock or Series E-1 Preferred Stock. As of June 25, 2021, there were outstanding 7,021,839 shares of our common stock and an aggregate of 14,986.59 shares of Series E Preferred Stock and Series E-1 Preferred Stock.

As of June 25, 2021, there were 2,475,000 shares of the Company’s common stock reserved under the Delcath Systems, Inc. 2020 Omnibus Equity Incentive Plan, of which 1,881,608 shares remained available to be issued. As of June 25, 2021, we had (a) 3,773,266 shares of common stock issuable upon the exercise of outstanding warrants, including (i) 11 common stock warrants, (ii) 1,765,355 Series E and Series E-1 Warrants, (iii) 1,851,900 Series F Warrants, and (iv) 156,000 Series F Pre-funded Warrants at a weighted average exercise price of $9.59 per share and (b) 1,091,891 shares of common stock issuable upon the exercise of outstanding options with a weighted average exercise price of $12.69 per share.

Common Stock

Voting rights. Our shares of common stock are entitled to voting rights for the election of directors and for all other matters requiring stockholder action. Each holder of common stock is entitled to one vote for each share, except as otherwise required by law, and subject to the rights of the holders of preferred stock. The common stock does not have cumulative voting rights.

Dividend rights. Holders of our common stock are entitled to receive such dividends, if any, as may be declared from time to time by our board of directors in its discretion out of funds legally available therefor. Holders of common stock share ratably in any dividends declared by our board of directors, subject to any preferential dividend rights of any outstanding preferred stock. Dividends consisting of shares of common stock may be paid to holders of shares of common stock. We do not intend to pay cash dividends in the foreseeable future.

Liquidation rights. Upon our liquidation or dissolution, the holders of our common stock will be entitled to receive, pro rata, all assets remaining available for distribution to stockholders after payment of all liabilities and provision for the liquidation of any shares of preferred stock at the time outstanding.

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We are required to pay certain fees and expenses that those securities will necessarily be offered or sold.

We may sell the securities separately or together:

We may sell the securities from time to time:

We will describe the method of distribution of the securities and the terms of the offering in the prospectus supplement. Any discounts or concessions allowed or re-allowed or paid to dealers may be changed from time to time.

If underwriters are used in the sale of any securities, the securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions described above. The securities may be either offeredwe incur incident to the public through underwriting syndicates represented by managing underwriters, or directly by underwriters. Generally, the underwriters’ obligations to purchase the securities will be subject to conditions precedent and the underwriters will be obligated to purchase all of the securities if they purchase anyregistration of the securities. We may use underwriters with whom we have a material relationship. We will describe inagreed to indemnify the prospectus supplement, naming the underwriter, the nature of any such relationship.

We may authorize underwriters, dealers or agents to solicit offers by certain purchasers to purchase the securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. The contracts will be subject only to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth any commissions we pay for solicitation of these contracts.

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LEGAL MATTERS

The legalityvalidity of the issuanceshares of Common Stock to be offered for resale by the securities being offered hereby and the binding nature of any debt securities, warrants or units being offered hereby is being passed upon by McCarter & English, LLP, Newark, New Jersey. The legality of the securities for any underwriters, dealers or agentsSelling Stockholder under this prospectus will be passed upon for us by counsel as may be specified in the applicable prospectus supplement.Cooley LLP, Boston, Massachusetts.

EXPERTS

The consolidated financial statements as of December 31, 20202021 and 20192020 and for each of the two years in the period ended December 31, 20202021 incorporated by reference in this prospectus have been so incorporated in reliance on the report of Marcum, LLP, an independent registered public accounting firm, incorporated herein by reference, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and does not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov.

You may also access our SEC filings at our website www.delcath.com. Our website and the information contained on, or that can be accessed through, our website will not be deemed to be incorporated by reference in, and are not considered part of, this prospectus. You should not rely on our website or any such information in making your decision whether to purchase our securities.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to incorporate by reference into this prospectus the information contained in other documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents. Any statement contained in any document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded, for purposes of this prospectus, to the extent that a statement contained in or omitted from this prospectus, or in any other subsequently filed document that also is or is deemed to be incorporated by reference herein, modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus. We incorporate by reference the documents listed below which have been filed by us:

All documents we file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, except as to any portion of any report or documents that is not deemed filed under such provisions, (1) on or after the date of filing of the registration statement containing this prospectus and prior to the effectiveness of the registration statement and (2) on or after the date of this prospectus until the earlier of the date on which all of the securities registered hereunder have been sold or the registration statement of which this prospectus is a part has been withdrawn, shall be deemed incorporated by reference in this prospectus and to be a part of this prospectus from the date of filing of those documents and will be automatically updated and, to the extent described above, supersede information contained or incorporated by reference in this prospectus and previously filed documents that are incorporated by reference in this prospectus.

Nothing in this prospectus shall be deemed to incorporate information furnished but not filed with the SEC pursuant to Item 2.02, 7.01 or 9.01 of Form 8-K. Upon written or oral request, we will provide without charge to each person, including any beneficial owner, to whom a copy of the prospectus is delivered a copy of any or all of the reports or documents incorporated by reference herein (other than exhibits to such documents, unless such exhibits are specifically incorporated by reference herein). You may request a copy of these filings, at no cost, by writing or telephoning us at the following address: Delcath Systems, Inc., 1633 Broadway, Suite 22C, New York, New York

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$100,000,000

Up to 1,257,705 Shares of

Common Stock

Preferred Stock

Senior Debt Securities

Warrants

Units Offered by the Selling Stockholders

PROSPECTUS

                , 20212022

We have not authorized any dealer, salesperson or other person to give any information or represent anything not contained in this prospectus. You must not rely on any unauthorized information. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus does not offer to sell any securities in any jurisdiction where it is unlawful. Neither the delivery of this prospectus, nor any sale made hereunder, shall create any implication that the information in this prospectus is correct after the date hereof.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.

The following table sets forth various expenses being borne by the Company in connection with the sale and distribution of the securities being registered. All of the amounts shown are estimates except for the Securities and Exchange Commission Registration Fee.

*To be provided by amendment or as an exhibit to a filing with the SEC under Section 13(a), 13(c) or 15(d) of the Securities Exchange Act of 1934, as amended.

The Company is incorporated under the laws of the State of Delaware. Section 102(b)(7) of Delaware’s General Corporation Law (the “DGCL”) allows a corporation to provide in its certificate of incorporation that a director of the corporation will not be personally liable to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except where the director breached the duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit. Our amended and restated certificate of incorporation provides for this limitation of liability.

Section 145 of the DGCL, or Section 145, provides that a Delaware corporation may indemnify any person who was, is or is threatened to be made, party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of such corporation), by reason of the fact that such person is or was an officer, director, employee or agent of such corporation or is or was serving at the request of such corporation as a director, officer, employee or agent of another corporation or enterprise. The indemnity may include expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by such person in connection with such action, suit or proceeding, provided such person acted in good faith and in a manner he reasonably believed to be in or not opposed to the corporation’s best interests and, with respect to any criminal action or proceeding, had no reasonable cause to believe that his or her conduct was illegal. A Delaware corporation may indemnify any persons who are, were or are a party to any threatened, pending or completed action or suit by or in the right of the corporation by reason of the fact that such person is or was a director, officer, employee or agent of another corporation or enterprise. The indemnity may include expenses (including attorneys’ fees) actually and reasonably incurred by such person in connection with the defense or settlement of such action or suit, provided such person acted in good faith and in a manner he reasonably believed to be in or not opposed to the corporation’s best interests, provided that no indemnification is permitted without judicial approval if the officer, director, employee or agent is adjudged to be liable to the corporation. Where an officer or director is successful on the merits or otherwise in the defense of any action referred to above, the corporation must indemnify him against the expenses which such officer or director has actually and reasonably incurred.

Section 145 further authorizes a corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation or enterprise, against any liability asserted against him and incurred by him in any such capacity, or arising out of his or her status as such, whether or not the corporation would otherwise have the power to indemnify him under Section 145.

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Article SEVENTH of the Company’s amended and restated certificate of incorporation provides that no person serving as a director of the Company shall be personally liable to the Company or its stockholders for breach of his or her fiduciary duty as a director, except where the director breached his duty of loyalty, failed to act in good faith, engaged in intentional misconduct or a knowing violation of law, authorized the payment of a dividend or approved a stock repurchase in violation of the DGCL or obtained an improper personal benefit.

Article EIGHTH of the Company’s amended and restated certificate of incorporation requires the Company to indemnify any person who may be indemnified by a Delaware corporation pursuant to Section 145 of the DGCL in each situation where the Company is permitted to indemnify such persons.

We have entered into indemnification agreements with our executive officers and directors pursuant to which we have agreed to indemnify such persons against all expenses and liabilities incurred or paid by such person in connection with any proceeding arising from the fact that such person is or was an officer or director of our company, and to advance expenses as incurred by or on behalf of such person in connection therewith.

The indemnification rights set forth above shall not be exclusive of any other right which an indemnified person may have or hereafter acquire under any statute, provision of our certificate of incorporation, our bylaws, agreement, vote of stockholders or disinterested directors or otherwise.

In addition, we maintain standard policies of insurance that provide coverage (1) to our directors and officers against loss rising from claims made by reason of breach of duty or other wrongful act and (2) to us with respect to indemnification payments that we may make to such directors and officers.

Item 16.

A list of exhibits filed with this registration statement on Form S-3 is set forth on the Exhibit Index and is incorporated herein by reference.

(ii) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(l)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in New York, New York, on June 25, 2021.September 7, 2022.

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutesPOWER OF ATTORNEY

We, the undersigned officers and appointsdirectors of Delcath Systems, Inc. hereby severally constitute and appoint Gerard Michel as attorney-in-fact,our true and lawful attorney with full power of substitution, in any and all capacities, to sign for us and in our names in the capacities indicated below the Registration Statement on Form S-3 filed herewith and any and all amendments (including post-effective amendments) to said Registration Statement, and post-effective amendments to thisany registration statement filed pursuant to Rule 462 under the Securities Act of 1933, as amended, in connection with said Registration Statement, and to file or cause to be filed the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, and generally to do all such things in our name and on our behalf in our capacities as officers and directors to enable Delcath Systems, Inc. to comply with the provisions of the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission, hereby ratifying and confirming all that said attorney-in-fact,attorney, or his substitute or substitutes, mayshall do or cause to be done by virtue thereof.hereof.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

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