As filed with the Securities and Exchange Commission on May 1, 2018

RegistrationNo. 333-224304July 16, 2019

Registration No. 333-_____

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORMS-3/A

(Amendment No. 1) S-3

REGISTRATION STATEMENT UNDER

UNDER

THE SECURITIES ACT OF 1933

Alphatec Holdings, Inc.

(Exact nameName of Registrant as specifiedSpecified in its charter)Its Charter)

Patrick S. Miles

Chief Executive Officer

Alphatec Holdings, Inc.

5818 El Camino Real

Carlsbad, CA 92008

(760)431-9286

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

Copies to:

Joshua E. Little, Esq.

Wayne D. Swan, Esq.

Durham Jones & Pinegar, P.C.

192 E. 200 N., Third Floor

St. George, Utah 84770

(435)674-0400

(801)297-1100 (Telephone) (801)415-3500 (Fax)

Approximate date of commencement of proposed sale to the public: From time to timepublic: As soon as practicable after the effective date of this registration statement becomes effective.statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  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.  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 statement 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, anon-accelerated filer, or a smaller reporting company or an emerging growth company.  See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company”company,” and “emerging growth company” in Rule12b-2 of the Exchange Act: (Check one):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)13(a) of the SecuritiesExchange Act.☐

CALCULATION OF REGISTRATION FEE

(1)Pursuant to Rule 416(a), this Registration Statement shall also cover any additional shares of the Registrant’s Common Stock that become issuable by reason of any stock dividend, stock split, recapitalization or other similar transaction effected without receipt of consideration that increases the number of the Registrant’s outstanding shares of common stock.

(2)  Pursuant to Rule 457(c), for all shares of Common Stock being registered hereunder with a sale price which cannot be presently determined, the Proposed Maximum Offering Price Per Share is $4.41 per share of Common Stock, which is based on the average of the high and low prices for the Registrant’s common stock as reported on the Nasdaq Global Select Market on July 12, 2019.

The Registrantregistrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the Registrantregistrant 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.

EXPLANATORY NOTE

This Amendment No. 1 to the Registration Statement on FormS-3SUBJECT TO COMPLETION, DATED JULY 16, 2019 (RegistrationNo. 333-224304) filed by Alphatec Holdings, Inc. on April 13, 2018 is being filed for the purpose of incorporating by reference the Company’s Definitive Proxy Statement filed on Schedule 14A on April 25, 2018, and the Company’s Form8-K/A filed on April 27, 2018.

ALPHATEC HOLDINGS, INC.PRELIMINARY PROSPECTUS

36,129,0604,838,710 Shares of

Common Stock

This prospectus coversmay be used only for the sale or other disposition from time to time of up to 36,129,0604,838,710 shares of our common stock $0.0001 par value per share (“Common Stock”), including:

In addition, this prospectus relates to an undetermined number of additional shares of our Common Stock issued or then issuable upon any stock split, dividend, or other distribution, recapitalization or similar event with respect to the foregoing, that may be offered from time to timeinterests therein by the Selling Stockholders.

The Selling Stockholders may, from time to time, sell, transfer, or otherwise dispose of any or all of their shares of Common Stock or interestsselling stockholders identified in shares of Common Stock on any stock exchange, market, or trading facility on which the shares are traded or in private transactions. These dispositions may be at fixed prices, at prevailing market prices at the time of sale, at prices related to the prevailing market price, at varying prices determined at the time of sale, or at negotiated prices.

Alphatec is not offering any shares of our Common Stock for sale under this prospectus.

We will not receive any of the proceeds from the sale or other disposition of the shares of our Common Stockcommon stock by the Selling Stockholders, other than anyselling stockholders.  We will, however, receive the proceeds from the cash exercisesale of the Merger Warrants, the Private Placement Warrants or the New Warrants by the Selling Stockholders to purchase shares of our Common Stockcommon stock to some of the selling stockholders to the extent they exercise for cash their warrants identified in this prospectus. We will pay the expenses incurred in registering the shares, including legal and accounting fees.

Except as set forth below, the price or prices at which are registered for resalethe selling stockholders may sell the shares will be determined by the Selling Stockholders under this prospectus.

We have paid the fees and expenses incident to the registration ofprevailing market price for the shares or in negotiated transactions.  The selling stockholders may sell shares directly to purchasers or through brokers or dealers. Brokers or dealers may receive compensation in the form of Common Stock for sale bydiscounts, concessions or commissions from the Selling Stockholders. Our registrationselling stockholders. See the “Plan of the shares of Common Stock covered by this prospectus does not mean that the Selling Stockholders will offer or sell any of the shares.Distribution” on page 6.

Our Common Stock is listedcommon stock trades on Thethe Nasdaq CapitalGlobal Select Market (“Nasdaq”) under the symbol “ATEC.” On April 11, 2018,July 12, 2019, the last reported salesales price of our Common Stockfor the common stock was $3.47$4.35 per share.

Investing in our securities involves risk. Please see “Risk Factors” on page 3 for a discussion of certain risks that you should consider in connection with an investment in the securities.

We may amend or supplement this prospectus from time to time by filing amendments or supplements as required. You should read the entire prospectus and any amendments or supplements carefully before you make your investment decision.INVESTING IN THE COMMON STOCK OFFERED IN THIS PROSPECTUS INVOLVES A HIGH DEGREE OF RISK. SEE “RISK FACTORS” ON PAGE 2 OF THIS PROSPECTUS.

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

The date of this Prospectus is __________, 2019.

This prospectus is dated May 1, 2018.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on FormS-3 under the Securities Act of 1933, as amended (the “Securities Act”), that we filed with the Securities and Exchange Commission (the “SEC”) using the “shelf” registration process. Under this shelf registration process, the Selling Stockholders named in this prospectus may offer and sell the securities described in this prospectus in one or more offerings.

You should rely only on the information contained in or incorporated by reference intoin this prospectus or any accompanying prospectus supplement. Neither we nor the Selling Stockholdersprospectus. We have not authorized anyone to provide you with different information. This document may only be used where it is legalIf anyone provides you with different or inconsistent information, you should not rely on it. The selling stockholders are not making an offer to sell these securities.securities in any jurisdiction where the offer or sale is not permitted. You should not assume that the information contained in this registration statement or any related prospectus, or inincluding any prospectus supplement,information incorporated herein by reference, is accurate as of any date other than itsthe date regardlesson the front of the time of delivery of the prospectusapplicable document, or prospectus supplementsuch earlier date as is expressly stated or any sale of the securities.

This prospectus and any accompanying prospectus supplement may include trademarks, service marks and trade names owned by us or other companies. All trademarks, service marks and trade names included in this prospectus are the property of their respective owners. As used in this prospectus, unless the context otherwise requires, all referencesapparent with respect to “we,” “us,” “our,” the “Company” and “Alphatec,” are to Alphatec Holdings, Inc., a Delaware corporation, and its subsidiaries, collectively. All references to “this prospectus” refer to this prospectus and any applicable prospectus supplement, unless the context otherwise requires.

WHERE YOU CAN FIND MORE INFORMATION

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 atwww.sec.gov and on our corporate website atwww.atecspine.com. Information on our website does not constitute part of this prospectus. You may inspect without charge any documents filed by us at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. You may obtain copies of all or any part of these materials from the SEC upon the payment of certain fees prescribed by the SEC. Please call the SEC at1-800-SEC-0330 for further information on the Public Reference Room.

DOCUMENTS INCORPORATED BY REFERENCE

The SEC allows us to “incorporate by reference” into this prospectus thesuch incorporated information in other documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus. Some information contained in this prospectus updates the information incorporated by reference, and information that we file subsequently with the SEC will automatically update this prospectus. In other words, in the case of a conflict or inconsistency between information set forth in this prospectus and information that we file later and incorporate by reference into this prospectus, you should rely on the information contained in theapplicable document, that was filed later.

In particular, we incorporate by reference into this prospectus the documents listed below (and any amendments thereto) and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (“Exchange Act”), after the initial filing of the registration statement that contains this prospectus and prior to the time that all the securities offered by this prospectus have been sold by the Selling Stockholders as described in this prospectus (other than, in each case, documents or information deemed to have been “furnished” and not “filed” in accordance with SEC rules) or such registration statement has been withdrawn:

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus will be deemed to be modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference in this prospectus modifies or supersedes that statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this prospectus.

You may request a copy of the registration statement, the above filings and any future filings that are incorporated by reference into this prospectus, other than an exhibit to a filing unless that exhibit is specifically incorporated by reference into that filing, at no cost to you, by writing or calling us at the following address:

Alphatec Holdings, Inc.

Attention: Corporate Secretary

5818 El Camino Real

Carlsbad, CA 92008

(760)431-9286

Except as provided above, no other information, including information on our website, is incorporated by reference in this prospectus.

INFORMATION REGARDING FORWARD-LOOKING STATEMENTS

The information in this prospectus, including information in documents incorporated by reference in this prospectus, includes statements of our expectations, intentions, plans and beliefs that constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act and are intended to come within the safe harbor protection provided by those sections. These statements, which involve risks and uncertainties, may relate to the discussion of our business strategies and our expectations concerning future operations and business plans, our future growth strategy, including our plans to expand, develop, or acquire particular operations or businesses, margins, profitability, trends, investing, financing activities for our future liquidity and capital resources, and to analyses and other information that are based on forecasts of future results and estimates of amounts not yet determinable. We have used words such as “may,” “will,” “should,” “expect,” “intend,” “plan,” “anticipate,” “believe,” “think,” “estimate,” “seek,” “predict,” “could,” “project,” “potential,” “continue” and other similar terms and phrases, including references to assumptions, in this prospectus to identify forward-looking statements. These forward-looking statements are made based on expectations and beliefs concerning future events affecting us and are subject to uncertainties, risks and factors relating to our operations and business environments, all of which are difficult to predict and many of which are beyond our control, that could cause our actual results to differ materially from those matters expressed or implied by these forward-looking statements. Such risks and other factors include those listed in the “Risk Factors” incorporated by reference into this prospectus from our Annual Report on Form10-K, as updated by subsequent reports.

You should read this prospectus, and the documents that we reference in this prospectus and which have been filed as exhibits to the registration statement of which this prospectus is a part, completely and with the understanding that our actual future results may be materially different from what we expect. The information

contained in this prospectus is accurate only as of the date of this prospectus, regardless of the time of delivery of this prospectus or any issuance or sale of our common shares.stock. Our business, financial condition, results of operations and prospects may have changed since any such date.

The terms “we,” “us,” “our” and the “company,” as used in this prospectus, refer to Alphatec Holdings, Inc., unless otherwise indicated.

DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

Some of the statements in this prospectus and in the documents incorporated by reference constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act. We use words like “anticipates,” “believes,” “plans,” “expects,” “future,” “intends,” “may,” “will,” “should,” “would,” “could,” “potential,” “continue,” “ongoing,” “estimates” and similar expressions to identify these forward-looking statements.

You should not place undue reliance on our forward-looking statements. We have based these forward-looking statements on our current expectations and projections about future events.  However, our actual results could differ materially from those anticipated in these forward-looking statements as a result of numerous risks and uncertainties that are beyond our control, including those we discuss in “Risk Factors,” the information incorporated therein by reference  and elsewhere in this prospectus and in the documents incorporated by reference in this prospectus. The information in this prospectus speaks only as of the date of this prospectus and the information incorporated herein by reference speaks only as of its date. Except as required by law, we do not assume anyundertake no obligation to update any forward-looking statements.statement, whether as a result of new information, future events or otherwise. You should not rely on these statements without also considering the risks and uncertainties associated with these statements and our business.

PROSPECTUS SUMMARY

This summary highlights information contained elsewhere in this prospectus and in the documents incorporated by reference. This summary does not contain all the information that you should consider before investing in our common stock. You should read this entire prospectus, including all documents incorporated by reference, carefully, especially “Risk Factors” and our consolidated financial statements and related notes incorporated by reference herein. Please see the section entitled “Where You Can Find More Information” on page 7 of this prospectus.

Our Business

We are a medical technology company focused on the design, development, and advancement of technology for better surgical treatment of spinal disorders. We are dedicated to revolutionizing the approach to spine surgery. We have a broad product portfolio designed to address the majority of U.S. market for fusion-based spinal disorder solutions. We intend to drive growth by exploiting our collective spine experience and investing in research and development to continually differentiate our solutions and improve spine surgery. We believe our future success will be fueled by introducing market-shifting innovation to the spine market, and we believe that we are well-positioned to capitalize on current spine market dynamics.

We market and sell our products in the U.S. through a network of independent distributors and direct sales representatives. An objective of our leadership team is to deliver increasingly consistent, predictable growth. To accomplish this, we have partnered more closely with new and existing distributors to create a more dedicated and loyal sales channel for the future. We have added, and intend to continue to add, new high-quality dedicated distributors to expand future growth. We believe this will allow us to reach an untapped market of surgeons, hospitals, and national accounts across the U.S., as well as better penetrate existing accounts and territories.

We have made significant progress in the transition of our sales channel since early 2017. Going forward, we intend to continue to relentlessly drive toward a fully exclusive network of independent and direct sales agents. Recent consolidation in the industry is facilitating the process, as large seasoned agents are seeking opportunities to re-enter the spine market by partnering with spine-focused companies that have broad, growing product portfolios.

Our common stock trades on the NASDAQ Global Select Market under the symbol “ATEC.” We had 47,656,406 shares issued and outstanding by 308 holders of record of our common stock as of July 12, 2019.

Our address is 5818 El Camino Real, Carlsbad, California, 92008.  Our telephone number is (760) 431-9286, and our internet website is located at https://atecspine.com/. The information on our website is not incorporated by reference into this prospectus nor is it part of this prospectus.   See the section entitled “Where You Can Find More Information” on page 7 of this prospectus.

The Offering

This prospectus covers up to 4,838,710 shares of common stock issuable upon exercise of warrants which we issued on June 21, 2019 to the selling stockholders.    

On June 21, 2019, in consideration of the selling stockholders providing capital to the Company pursuant to that certain First Amendment to Credit, Security and Guaranty Agreement dated March 27, 2019, we issued to the selling stockholders new warrants exercisable for an aggregate of 4,838,710 shares of common stock at an exercise price of $2.17 per share, which we refer to as the 2019 Warrants.  The 2019 Warrants are exercisable from June 21, 2019 through June 21, 2026.  The 2019 Warrants contain provisions which would adjust the exercise price, and in inverse proportion adjust the number of shares of common stock subject to the 2019 Warrants, in the event we pay stock dividends, effect stock splits or complete other transactions specified in the 2019 Warrants. The 2019 Warrants also contain provisions which would adjust the exercise price and the number of shares of common stock subject to the 2019 Warrants if we issue shares of common stock or securities exercisable for or convertible into shares of common stock at prices below the exercise price of the 2019 Warrants at the time of such issuance, subject to specified exceptions.

We also agreed to file a registration statement, of which this prospectus is a part, on or before July 21, 2019, to register for resale the shares that may be issued upon exercise of the 2019 Warrants.  We have also agreed to have the registration statement declared effective as soon as possible and in any event between 60 and 90 days after June 21, 2019.  Once the registration statement is declared effective we have agreed to use our best efforts to keep it effective until all of the shares covered by this prospectus have been sold or may be sold without volume or manner-of-sale restrictions in accordance with Rule 144 under the Securities Act and with the requirement for us to be in compliance with the correct public information requirement of Rule 144 under the Securities Act.  If the registration

statement is not declared effective within 90 days following the date of issuance of the securities, or the warrant selling stockholders are otherwise unable to re-sell the shares purchased upon exercise of the 2019 Warrants, we will be obligated to pay liquidated damages to the selling stockholders until the selling stockholders are again able to re-sell the shares purchased upon exercise of the 2019 Warrants.

We will not receive any proceeds from the sale of securities by the selling stockholders. See “Use of Proceeds” on page 3 of this prospectus.

RISK FACTORS

PleaseBefore deciding to purchase, hold or sell our common stock, you should carefully consider the risk factors describedrisks, cautionary statements and other information contained in this prospectus and in our other filings with the Securities and Exchange Commission (the “SEC”) that we incorporate by reference, including our Annual Report on Form10-K for the fiscal year ended December 31, 20172018.  The risks and periodic reports filed withuncertainties described in these documents are not the SEC, which are incorporated by reference in this prospectus. Before making an investment decision, you should carefully consider these risks as well as other informationonly ones we include or incorporate by reference in this prospectus or include in any applicable prospectus supplement.face.  Additional risks and uncertainties not presently known to us or that we currently deem currently immaterial may also impairaffect our business.  If any of these known or unknown risks or uncertainties actually occurs with material adverse effects on our company, our business, operations or adversely affect ourfinancial condition, results of operations operation and/or financial condition.liquidity could be seriously harmed.  In that event, the market price for our common stock will likely decline, and you may lose all or part of your investment.

USEINCORPORATION OF PROCEEDSCERTAIN INFORMATION BY REFERENCE

We have elected to “incorporate by reference” certain information into this prospectus. By incorporating by reference, we can disclose important information to you by referring you to another document we have filed with the SEC. The Selling Stockholdersinformation incorporated by reference is deemed to be part of this prospectus, except for information incorporated by reference that is superseded by information contained in this prospectus. This prospectus incorporates by reference the documents set forth below that we have previously filed with the SEC:

Certain Current Reports on Form 8-K dated both prior to and after the date of this prospectus are or will receivebe furnished to the SEC and shall not be deemed “filed” with the SEC and will not be incorporated by reference into this prospectus. However, all other reports and documents filed by us after the date of this prospectus under Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act, prior to the termination of the offering of the securities covered by this prospectus will also be deemed incorporated by reference in this prospectus and considered to be part of this prospectus from the date those documents are filed.

You should read the information relating to us in this prospectus together with the information in the documents incorporated by reference.

You may obtain a copy of any of the above-referenced documents, at no cost, from our website at https://atecspine.com/.  The information contained in, or that can be accessed through, our website is not part of this prospectus.  We will also furnish without charge to you, on written or oral request, a copy of any or all of the net proceeds from the sale of their Common Stock under this prospectus,documents incorporated by reference, including the Common Stock underlying the Series B Preferred Stock, the Merger Warrants, and the Private Placement Warrants. exhibits to these documents.  You should direct your requests for documents to:

Alphatec Holdings, Inc.
Attn: Corporate Secretary
5818 El Camino Real
Carlsbad, CA 92008
(760) 431-9286

USE OF PROCEEDS

We will not receive any of the proceeds from the sale of the Common Stock by the Selling Stockholders.

The Selling Stockholders will pay any underwriting discounts and commissions and expenses incurred by the Selling Stockholders for brokerage, accounting, tax, legal services or any other expenses incurred by the Selling Stockholders in disposing of these shares. We will bear all other costs, fees and expenses incurred in effecting the registration of the shares covered by this prospectus.

SELLING STOCKHOLDERS

Shares Issued to Certain Selling Stockholders in the Merger

On March 6, 2018, the Company and its newly-created wholly-owned subsidiary, Safari Merger Sub, Inc. (“Sub”), entered into the Merger Agreement with SafeOp, certain key stockholders of SafeOp, and a stockholder representative. The Merger Agreement provided for the Merger, which was consummated on March 8, 2018, in which Sub was merged into SafeOp, with SafeOp being the surviving corporation and a wholly-owned subsidiary of the Company. Under the terms of the Merger Agreement, the Company paid to the former stockholders of SafeOp $15 million in cash, the Merger Closing Shares, the Merger Notes that are convertible into the Merger Shares and the Merger Warrants to purchase the Merger Warrant Shares at an exercise price of $3.50 per share. An additional 443,421 shares of Common Stock are issuable upon achievement of certain post-closing milestones (the “First Milestone Merger Shares”), and 886,842 shares of Common Stock are issuable upon achievement of certain additional post-closing milestones (the “Second Milestone Merger Shares”). The Merger Closing Shares, Merger Note Shares, Merger Warrant Shares, First Milestone Merger Shares, and Second Milestone Merger Share are referred to collectively as the “Merger Shares.” The closing of the Merger (the “Closing”) occurred simultaneous with the closing and funding of the Private Placement described below.

Prior to the Merger there were no material relationships between the Company and SafeOp or any affiliates of the Company and SafeOp. The Merger Agreement contains customary representations, warranties and covenants by SafeOp and the Company, as well as customary indemnification provisions among the parties.

Shares Issued to Certain Selling Stockholders in the Private Placement

On March 8, 2018, the Company entered into a securities purchase agreement (the “Securities Purchase Agreement”) pursuant to which the Company sold in the Private Placement to certain institutional and accredited investors (collectively, the “Purchasers”), including certain directors and executive officers of the Company, at a purchase price of $1,000 per share, 45,200 shares (the “Series B Preferred Shares”) of its newly designated Series B Preferred Stock, and the Private Placement Warrants to purchase the Private Placement Warrant Shares at an exercise price of $3.50 per share.

The Series B Preferred Shares will be converted automatically into the Series B Preferred Conversion Shares at a conversion price of $3.15 per share (subject to adjustment as described below and in the Series B Designation of Rights (as defined below)) upon approval by the Company’s stockholders (the “Stockholder Approval”) at the 2018 Annual Meeting of Stockholders as required in accordance with the Nasdaq rules described below. The Private Placement Warrants will become exercisable following Stockholder Approval, are subject to certain ownership limitations in certain cases, and expire five years after the date of the Stockholder Approval. The Series B Preferred Conversion Shares and the Private Placement Warrant Shares are referred to collectively as the “Private Placement Shares.”

The aggregate gross proceeds from the Private Placement were $45.2 million. The Company used a portion of the Private Placement proceeds to fund the cash consideration paid in the Merger. The Company intends to use the balance of the net proceeds from the Private Placement for general corporate and working capital purposes, and to fund additional strategic initiatives.

The rights and preferences of the Series B Preferred Stock are designated by the Company’s Board of Directors in the Certificate of Designation of Preferences, Rights, and Limitations of the Series B Preferred Stock of Alphatec Holdings, Inc. (the “Series B Designation of Rights”).

Each share of Series B Preferred Stock has $0.0001 par value per share and a stated value of $1,000, with the aggregate stated value of all shares of Series B Preferred Stock being $45.2 million.

The Series B Preferred Stock will be entitled to dividends on anas-if-converted basis in the same form as any dividends actually paid on shares of Common Stock or other securities. In addition, until the earlier of the date there are no shares of Series B Preferred Stock outstanding, or one year from the effective date of this registration statement, the conversion price in respect of the Series B Preferred Stock is also subject to anti-dilution protection adjustment in the event the Company issues securities at an effective price less than the initial conversion price thereof, subject to certain exceptions. If the Stockholder Approval is not obtained, the shares of Series B Preferred Stock will not become convertible, and will remain outstanding in accordance with the terms of the Series B Designation of Rights.

Except as otherwise required by law, the holders of Series B Preferred Stock will have no right to vote on matters submitted to a vote of the Company’s stockholders. Without the prior written consent of 75% of the outstanding shares of Series B Preferred Stock, however, the Company may not: (a) alter or change adversely the powers, preferences or rights given to the Series B Preferred Stock or alter or amend the Series B Designation of Rights; (b) amend the Company’s certificate of incorporation or other charter documents in any manner that adversely affects any rights of the holders of Series B Preferred Stock; (c) increase the number of authorized shares of Series B Preferred Stock; or (d) enter into any agreement with respect to any of the foregoing.

In the event of the dissolution and winding up of the Company, the proceeds available for distribution to the Company’s stockholders shall be distributedpari passu among the holdersdisposition of the shares of Common Stock and Series B Preferred Stock, pro rata based upon the number of shares heldcommon stock or interests therein offered by each such holder, as if the outstanding shares of Series B Preferred Stock were converted into shares of Common Stock.

Shares Issued to a Selling Stockholder in Connection with the Warrant Exercise Agreement

On March 8, 2018, the Company entered into the Warrant Exercise Agreement with the Warrant Holder to purchase up tothis prospectus.  We will issue an aggregate of 2.4 million4,838,710 shares of Common Stock, at an exercise price of $2.00 per share (the “Original Warrant”). Pursuant to the terms of the Warrant Exercise Agreement, the Warrant Holder agreed to exercise, from time to time and in accordance with the terms of the Original Warrant, including certain beneficial ownership limitations set forth therein, the Original Warrant for cash (the “Warrant Exercise”). As a result of the Warrant Exercise, the Company received gross proceeds of $3.4 million on March 8, 2018 from the exercise of 1.7 million shares under the Original Warrant, and expects to receive additional gross proceeds of up to $1.4 million thereafter from additional exercises of the remaining shares under the Original Warrant following Stockholder Approval. The Company expects to use the net proceeds from the exercise of the Original Warrant for general corporate and working capital purposes and to fund strategic initiatives.

Pursuant to the terms of the Warrant Exercise Agreement, and in order to induce the Warrant Holder to exercise the Original Warrant, the Company issued the New Warrants to the Warrant Holder. The New Warrants entitle the Warrant Holder to purchase a number of shares of Common Stock equal to 75% of the number of shares of Common Stock receivedcommon stock potentially offered by the Warrant Holder upon the full cash exercise of the Original Warrant (i.e., 75% of 2,400,000 shares of Common Stock, or 1,800,000 shares of Common Stock). The terms of the New Warrants are substantially similar to the terms of the Private Placement Warrants, and have an exercise price of $3.50 per share.

The New Warrants will become exercisable following Stockholder Approval, are subject to certain ownership limitations, and expire five years after the date of Stockholder Approval.

Registration Rights Agreement

In connection with the Private Placement, the Merger, and the Warrant Exercise Agreement, the Company entered into a registration rights agreement (as amended, the “Registration Rights Agreement”) with the Purchasers, the former stockholders of SafeOp, and the Warrant Holder (collectively, the “Holders”), effective as of the Closing. Pursuant to the Registration Rights Agreement, the Company agreed to prepare and file a registration statement with the SEC (the “Resale Registration Statement”) by April 16, 2018 for purposes of registering the resale of the Private Placement Shares, the Merger Shares, and the New Warrant Shares. Thisthis prospectus is part of the Resale Registration Statement filed in furtherance of our obligations under the Registration Rights Agreement.

Support Agreements

In connection with the Private Placement, the Merger and the Warrant Exercise Agreement, certain stockholders of the Company then comprising a majority of the outstanding shares of Common Stock entered into support agreements (the “Support Agreements”) pursuant to which such stockholders agreed to vote all shares of Common Stock owned by them in favor of the Company’s issuances of the Merger Shares in connection with the Merger, Private Placement Shares in connection with the Private Placement, and New Warrant Shares in connection with the New Warrants. Accordingly, a sufficient number of stockholders signed the Support Agreements to ensure approval of the Company’s issuance of the Merger Shares in connection with the Merger, the Private Placement Shares in connection with the Private Placement, and the New Warrant Shares in connection with the New Warrants.

Stockholder Approval Requirements

The Company’s issuances of Merger Shares, Private Placement Shares and New Warrant Shares are subject to the Stockholder Approval requirements summarized below. Until we have obtained Stockholder Approval, we will not issue Merger Shares, Private Placement Shares or New Warrant Shares in excess of 19.9% of the issued

and outstanding shares of Common Stock of the Company prior to the Merger and Private Placement. Also, until Stockholder Approval has been obtained, the Company will not issue any Private Placement Shares to any “Insiders” of the Company (officers, directors, employees, consultants), at prices less than the fair market value of the Company’s Common Stock. Accordingly, the Company will not issue any Merger Note Shares, Second Milestone Shares, Merger Warrant Shares, Series B Conversion Shares, Private Placement Warrant Shares or New Warrant Shares until we have obtained Stockholder Approval.

Our Common Stock is listed on The Nasdaq Capital Market (“Nasdaq”) and we are subject to the Nasdaq Listing Rules (“Nasdaq Rules”) governing listing requirements (Section 5500 of the Nasdaq Rules for securities listed on the Capital Market) and corporate governance (Section 5600 of the Nasdaq Rules) of companies with securities listed on Nasdaq. Pursuant to the terms of both the Merger Agreement and the Securities Purchase Agreement, we have covenanted to obtain approval of our stockholders as may be required by the Nasdaq Rules.

Nasdaq Rules 5635(a), (b) and (d), apply to the issuance of shares of our Common Stock (or securities convertible into or exercisable for Common Stock):

(A) representing more than 19.99% of the outstanding Common Stock or voting power of the Company in connection with: (i) the acquisition of SafeOp pursuant to the Merger; (ii) the Company’s issuance of shares of Common Stock upon the conversion of the of Series B Preferred Stock and related exercise of the Private Placement Warrants; and (iii) the Company’s issuance of shares of Common Stockonly upon the exercise of the New Warrants;

(B) in connection with2019 Warrants by the Securities Purchase Agreement to Insiders at less than market prices; and

(C) in connection withselling stockholders.  If the Merger, the Securities Purchase Agreement and the Warrant Exercise Agreement that could result in a Nasdaq Change in Control.

Common Stock issuances referred to in (A) through (C) above would occur with respect to:

Nasdaq Listing Rule 5635(a) (the “20% Acquisition Rule”) requires that an issuer obtain stockholder approval prior to2019 Warrants, the issuanceselling stockholders have not had any material relationship with us within the past three years.

The table below lists the selling stockholders and other information regarding the beneficial ownership of the shares of common stock in connection with the acquisitionby each of the stock or assets of another company if, due to the present or potential issuance of common stock, including shares issued pursuant to anearn-out provision or similar type of provision, or securities convertible into or exercisable for common stock: (i) the common stock has or will have upon issuance voting power equal to or in excess of 20% of the voting power outstanding before the issuance of stock or securities convertible into or exercisable for common stock; or (ii)selling stockholders. The second column lists the number of shares of common stock to be issued is or will be equal to or in excess of 20%beneficially owned by each selling stockholder, based on its ownership of the shares of common stock and warrants, as of July 15, 2019, assuming exercise of the 2019 Warrants held by the selling stockholders on that date, without regard to any limitations on exercise. The third column lists the shares of 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 covers the resale of the sum the maximum number of shares of common stock outstanding before the issuanceissuable upon exercise of the stock or securities. The issuance2019 Warrants, determined as if the outstanding 2019 Warrants were exercised in full as of the Merger Closing Shares, andtrading day immediately preceding the potential issuance of the First Milestone Merger Shares, represent issuances by the Company of less than 19.99% of our issued and outstanding Common Stock, and thus could be effected prior to and without Stockholder Approval. However, for purposes of analyzing application of the Nasdaq stockholder approval rules, and compliance with Nasdaq Rule 5635(a) in particular, the Company is aggregating the Merger Shares, the Private Placement Shares and the New Warrant Shares. The proceeds from the sale of the Series B Preferred Stock and the Private Placement Warrants were used, in part, to finance the Merger, and the Merger Shares were issued as part of the consideration paid to the former stockholders of SafeOp in connectiondate this registration statement was initially filed with the Merger. Thus,SEC, and subject to adjustment as provided in the conversion of the Merger Notes,2019 Warrants, without regard to any limitations on the exercise of the Merger Warrants and2019 Warrants. The fourth column assumes the potential

issuancesale of the Second Milestone Merger Shares (all in connection with the Merger), the automatic conversion of the Series B Preferred Stock and the exercise of the Private Placement Warrants in connection with the Private Placement, and the exercise of the New Warrants will result in the issuance of our Common Stock representing in excess of 20% of the voting power, and 20% of the number of shares of our Common Stock, in each case, outstanding, before the Merger and the Private Placement.

Nasdaq Listing Rule 5635(d) (the “20% Private Placement Rule”) requires that an issuer obtain stockholder approval prior to the issuance of common stock if such issuance is for less than the greater of book or market value of the common stock and would equal 20% or more of the common stock or voting power of the issuer outstanding before the issuance. The conversion price of the Series B Preferred Stock is less than the greater of the book or market value of our Common Stock immediately before we entered into the Securities Purchase Agreement. In addition, the terms of the Series B Preferred Stock and the Securities Purchase Agreement include anti-dilution adjustments that could result in a reduction of the conversion price, or the issuance of additional shares of Common Stock, in the future. Furthermore, the issuance of our Common Stock upon conversion of the Series B Preferred Stock and exercise of the Private Placement Warrants will exceed 20% of our Common Stock currently outstanding.

Nasdaq Listing Rule 5635(c) (the “Insider Equity Compensation Rule”) requires that we obtain stockholder approval prior to issuing shares of common stock to Insiders of the Company at less than market price, including issuance of our Common Stock upon conversions of the Series B Preferred Stock at the current conversion price of $3.15 per share, and potential anti-dilution issuances of Common Stock to any such Insiders pursuant to the provisions of the Securities Purchase Agreement. Accordingly, Stockholder Approval will include approval at the Company’s Annual Meeting to issue the Series B Preferred Conversion Shares, the Private Placement Warrant Shares, and shares of Common Stock pursuant to any anti-dilution protection provisions of the Securities Purchase Agreement or Series B Designation of Rights, to Insiders of the Company, when Common Stock is issued in such transactions at less than market value.

In addition, Nasdaq Listing Rule 5635(b) requires prior stockholder approval for issuances of securities that could result in a “change of control” of the issuer (the “Change of Control Rule”). Nasdaq may deem a change of control to occur when, as a result of an issuance, an investor or a group would own, or have the right to acquire, 20% or more of the outstanding shares of common stock or voting power, and such ownership or voting power of an issuer would be the largest ownership position of the issuer (a “Nasdaq Change of Control”). Upon securing Stockholder Approval and triggering the automatic conversion of the Series B Preferred Stock,L-5 Healthcare Partners, LLC (“L-5 Healthcare”), as the lead purchaser in the Private Placement, would own in excess of 20% of the outstanding shares of Common Stock or voting power of the Company. Stockholder Approval is necessary to satisfy the requirements of the Change of Control Rule, as that rule would be triggered by the issuance of Common Stock toL-5 Healthcare upon conversion of its Series B Preferred Stock and the exercise of its Private Placement Warrants.

Selling Stockholders

This prospectus covers the public resale of the shares of Common Stock owned or to be acquired by the Purchasers in connection with the Private Placement, by the former SafeOp stockholders in connection with the Merger, and by the Warrant Holder listed in the table below as the selling stockholders (together with their transferees, pledgees, donees, or successors, the “Selling Stockholders”). The Selling Stockholders may from time to time offer and sell pursuant to this prospectus any or all of the shares of Common Stock owned by them identified in the table. The Selling Stockholders may sell some, all or none of the shares covered by this prospectus, and they and we make no representation that the shares will be offered for sale. The table below presents information regarding the Selling Stockholders and the shares that they may offer and sell from time to time under this prospectus.

The following table sets forth:

All information with respect to Common Stock ownership of the Selling Stockholders has been furnished by or on behalf of the Selling Stockholders and is as of April 11, 2018. We believe, based on information supplied by the Selling Stockholders, that except as may otherwise be indicated in this section, each of the Selling Stockholders and its affiliates identified herein have sole voting and dispositive power with respect to the Common Stock reported as beneficially owned by it. Because the Selling Stockholders may sell some or all of the shares included in this prospectus, and because there are currently no agreements, arrangements or understandings with respect to the sale of any of the shares, no estimate can be given as to the number of shares available for resale hereby that will be held by the Selling Stockholders in the future. In addition, the Selling Stockholders may have sold, transferred or otherwise disposed of, or may sell, transfer or otherwise dispose of, at any time and from time to time, the Common Stock they hold in transactions exempt from the registration requirements of the Securities Act after the date on which it provided the information set forth on the table below. We have, therefore, assumed for the purposes of the following table, that each Selling Stockholder will sell all of the shares owned beneficially by it listed in the table below that are covered by this prospectus.

Under the terms of the Private Placement2019 Warrants, and the New Warrants, the Selling Stockholders, unless they elect otherwise,a selling stockholder may not exercise the Private Placement Warrants or the New2019 Warrants to the extent such conversion or exercise would cause the Selling Stockholder,such selling stockholder, together with its affiliates and attribution parties, to beneficially own a number of shares of Common Stockcommon stock which would exceed the applicable beneficial ownership limitation set forth therein (4.99% or, at the election4.99% of the holder, 9.99%) (the “Beneficial Ownership Limitation”),our then outstanding common stock following such exercise, excluding for purposes of such determination shares of Common Stockcommon stock issuable upon exercise of the Private Placement Warrants or the New2019 Warrants which have not been exercised. However, theThe number of shares in the second column of the table below assumes full exercise of the Private Placement Warrants and the New Warrants held by the Selling Stockholders, and does not reflect the application of the Beneficial Ownership Limitation to the exercise of the Private Placement Warrants and the New Warrants as set forth in this paragraph.

limitation. The third column of the table lists the shares of Common Stock being offered by this prospectus by the Selling Stockholders.

In accordance with the terms of the Registration Rights Agreement with the Selling Stockholders, this prospectus generally covers the resale of the sum of (i) the Merger Closing Shares, (ii) the Merger Note Shares, (iii) the Milestone Shares, (iv) the Merger Warrant Shares, without regard to any limitations on the exercise of the Merger Warrants, (v) the Series B Conversion Preferred Shares, (vi) the Private Placement Warrant Shares, without regard to any limitations on the exercise of the Private Placement Warrants, (vii) the New Warrant Shares, without regard to any limitations on the exercise of the New Warrants and (viii) an indeterminate number of additional shares of Common Stock issued or then issuable upon any stock split, dividend, or other distribution, recapitalization or similar event with respect to the forgoing. The Selling Stockholdersselling stockholders may sell all, some or none of their shares in this offering. See “Plan of Distribution,Distribution.” below.

Beneficial ownership for the purposesEach of the tableselling stockholders that is determined in accordanceaffiliated with a registered broker-dealer purchased the rules and regulations of the SEC. The SEC rules regarding beneficial ownership determination generally provide that a person is the “beneficial owner” of securities if such person has or shares the power to vote or direct the voting thereof, or to dispose or direct the disposition thereof, or has the right to acquire such powers within 60 days. At our 2018 Annual Meeting of Stockholders, we are seeking Stockholder Approval of the issuance of Merger Note Shares,

Milestone Shares, Merger Warrant Shares, Series B Preferred Conversion Shares, Private Placement Warrant Shares and New Warrant Shares, all as described above. Certain stockholders of the Company comprising a majority of the outstanding shares of Common Stock entered into the Support Agreement in connection with the Merger the Private Placement and the Warrant Exercise Agreement as describe above. However, notwithstanding the Support Agreements, we cannot determine with certainty at this time whether, or if, Stockholder Approval will be secured within 60 days of the date of this registration statement. For purposes only of the table calculations presented below, we assume that the Company will secure the Stockholder Approval, and that the Selling Stockholders are therefore the beneficial owners of all Merger Shares, Private Placement Shares and New Warrant Shares. Except as disclosedoffered hereby in the table, we believe thatordinary course of business and does not have any agreement or understandings, directly or indirectly, to distribute the Selling Stockholders and their affiliates identified herein possess sole voting and investment power over all shares of Common Stock shown as beneficially ownedoffered by such Selling Stockholders and affiliates.this prospectus.

SELLING STOCKHOLDERS TABLE__________

Each time a Selling Stockholder sells any securities offered by this prospectus, the Selling Stockholder is required to provide you with this prospectus and, to the extent required, a related prospectus supplement containing specific information about such Selling Stockholder and the terms of the securities being offered in the manner required by the Securities Act. Any prospectus supplement will, to the extent required, set forth the following information with respect to the Selling Stockholder:

No offer or sale may occur unless the registration statement that includes this prospectus has been declared effective by the SEC and remains effective at the time a Selling Stockholder offers or sells Common Stock. We are required, under certain circumstances, to update, supplement or amend this prospectus to reflect material developments in our business, financial position and results of operations and may do so by an amendment to this prospectus, a prospectus supplement or a future filing with the SEC incorporated by reference in this prospectus.

DESCRIPTION OF CAPITAL STOCK

The following descriptions are summaries of material terms of our Common Stock, preferred stock, articles of incorporation and bylaws. This summary is qualified by reference to our articles of incorporation, bylaws and the Series B Designation of Rights, which are filed or incorporated by reference as exhibits to the registration statement of which this prospectus forms a part, and by the provisions of applicable law.

As of April 11, 2018, our authorized capital stock was as follows:

In addition, as of April 11, 2018:

In addition to the descriptions set forth below, please refer to our other publicly filed documents incorporated herein by reference, which describe our other outstanding preferred stock,underlying warrants registration rights, equity incentive plans and other securities.

Common Stock

Subject to any special voting rights of any series of preferred stock that we may issue in the future, each share held of record of Common Stock has one vote on all matters voted on by our stockholders, including the election of our directors. Because holders of Common Stock do not have cumulative voting rights, the holders of a majority of the shares of Common Stock can elect all of the members of the Board of Directors standing for election, subject to the rights, powers and preferences of any outstanding series of preferred stock.

No share of Common Stock affords any preemptive rights or is convertible, redeemable, assessable or entitled to the benefits of any sinking or repurchase fund. Holders of Common Stock will be entitled to dividends in the amounts and at the times declared by our Board of Directors in its discretion out of funds legally available for the payment of dividends.

Holders of Common Stock are entitled to receive dividends when, as and if declared by the Board of Directors out of funds legally available therefor, subject to any dividend preferences of any outstanding shares of preferred stock. Holders of Common Stock will share equally in our assets on liquidation after payment or provision for all liabilities and any preferential liquidation rights of any preferred stock then outstanding. All outstanding shares of Common Stock are fully paid andnon-assessable. Our Common Stock is traded on Nasdaq under the symbol “ATEC.”

Stockholder Agreements

The Securities Purchase Agreementprovides L-5 Healthcare the right to appoint (i) up to two members of the Board of Directors of the Company (the “Board”) for so long as theL-5 Group (as defined below) continues to hold collectively at least 12.5% of the Company’s fully diluted Common Stock, and (ii) one member of the Board for so long as theL-5 Group continues to hold collectively at least 7.5% of the Company’s fully diluted Common Stock but less than 12.5% of the Company’s fully diluted Common Stock. The Securities Purchase Agreement also provides that one member of the Board appointed byL-5 Healthcare, as applicable, shall be permitted to attend as an observer any meetings of traditional Board committees.

Additionally, pursuant to the terms of the Securities Purchase Agreement, the Company granted toL-5 Healthcare and its affiliates and their respective members, stockholders, owners, equity holders and family members (collectively, the “L-5 Group”), so long as theL-5 Group continues to hold collectively at least 12.5% of the Company’s fully diluted Common Stock, the right to purchase on the terms and subject to the conditions set forth in the Securities Purchase Agreement, each such stockholder’s pro rata share of any shares of Common Stock or securities exercisable for or convertible into Common Stock issued by the Company, other than such securities issued in any exempt issuance specified in the Securities Purchase Agreement.

Transfer Agent and Registrar

The transfer agent and registrar for our Common Stock is Computershare, Inc., with a mailing address of 480 Washington Ave., Jersey City, NJ 07310.

Preferred Stock

As of the date of this prospectus, we have 20,000,000 shares of authorized preferred stock, of which 15,245 have been designation as Series A Preferred Stock, 4,044 of which are currently outstanding, and 45,200 have been designated as Series B Convertible Preferred Stock, 45,200 of which are currently outstanding. At the

direction of our Board of Directors, we may issue shares of preferred stock from time to time. Our Board of Directors may, without any action by holders of our Common Stock:

The rights of any class or series of preferred stock may include, among others:

We may issue shares of, or rights to purchase, preferred stock, the terms of which might:

Any of these actions could discourage a transaction that some or a majority of our stockholders might believe to be in their best interests or in which our stockholders might receive a premium for their stock over its then market price.

Series A Convertible Preferred Stock

The following is a summary of the terms of the Series A Designation of Rights filed with the Secretary of State of the State of Delaware in March 2017. A total of 15,245 shares of Series A Convertible Preferred Stock are authorized for issuance and a total of 4,043.3460 shares of Series A Convertible Preferred Stock are outstanding as of April 11, 2018. The shares of Series A Convertible Preferred Stock have a stated value of $1,000 per share and are convertible into2,419,355 shares of our common stock, atwith an initial conversionexercise price of $2.00 per share.

Holders of the Series A Convertible Preferred Stock are entitled$2.17, and expiring on June 21, 2026, and shares underlying warrants to dividends on anas-if converted basis in the same form as any dividends actually paid on shares of our common stock.

The shares of Series A Convertible Preferred Stock will be convertible, at the option of each holder, at any time or from time to time intopurchase 389,000 shares of our common stock, at the conversion price in effect at the time of conversion, except that, subject to certain limited exceptions, no holder of Series A Convertible Preferred Stock may convert the Series A Convertible Preferred Stock if, after giving effect to the conversion, the holder and all affiliated persons would own beneficially more than 4.99% of our common stock (subject to adjustment up to 9.99% solely at the holder’s discretion upon 61 days’ prior notice to us). The initial conversion price of $2.00 is subject to appropriate adjustment in the event of a stock split, stock dividend, combination or other recapitalization affecting our common stock.

Except as otherwise required by law, the holders of Series A Convertible Preferred Stock have no right to vote on matters submitted to a vote of our stockholders. Without the affirmative vote of the holders of 75% of the

outstanding shares of Series A Convertible Preferred Stock, however, we may not: (1) amend our restated certificate of incorporation, as amended, (including the Certificate of Designation) in a manner adverse to the Series A Convertible Preferred Stock; (ii) increase the number of authorized shares of preferred stock, or (iii) enter into any agreement with respect to any of the foregoing.

In the event of the dissolution and winding up of the Company, the proceeds available for distribution to the Company’s stockholders shall be distributedpari passu among the holders of the shares of Common Stock and Series A Convertible Preferred Stock, pro rata based upon the number of shares held by each such holder, as if the outstanding shares of Series A Convertible Preferred Stock were convertible, and were converted, into shares of Common Stock.

Series B Convertible Preferred Stock

The following is a summary of the terms of the Series B Designation of Rights filed with the Secretary of State of the State of Delaware on March 8, 2018 in connection with closing the Private Placement. We encourage you to read the Series B Designation of Rights thoroughly; the following summary is qualified in its entirety by reference to the actual terms contained in the Series B Designation of Rights.

A total of 45,200 shares of Series B Preferred Stock are authorized for issuance under the Series B Designation of Rights. Each share of Series B Preferred Stock has a stated value of $1,000 and is convertible into approximately 317 shares of the Company’s Common Stock at a conversion price per share of $3.15. Until the date that Stockholder Approval is obtained, the Purchasers will be unable to convert their Series B Preferred Shares into Common Stock, in accordance with Nasdaq rules and regulations. Upon Stockholder Approval, the Series B Preferred Shares will automatically convert into shares of Common Stock.

The Series B Preferred Stock will be entitled to dividends on anas-if-converted basis in the same form as any dividends actually paid on shares of Common Stock or other securities.

The initial conversion exercise price of $3.15, and expiring on November 6, 2025. Tawani Holdings LLC is subject to appropriate adjustment inan Illinois limited liability company, which is ninety-nine per cent (99%) owned by the event of a stock split, stock dividend, combination, reclassification or other recapitalization affectingJennifer N. Pritzker Revocable Trust u/a/d Feb 21 1986, as amended (the “Trust”), and one percent (1%) owned by Tawani Enterprises Inc., an Illinois corporation. Tawani Enterprises Inc. is wholly owned by the Common Stock. In addition, untilTrust. Jennifer N.

Pritzker is grantor and the earliertrustee of the date there are no sharesTrust. The address of Series B Preferred Stock outstanding, or one year from the effective date of the Resale Registration Statement, the conversion priceTawani Holdings LLC is also subject anti-dilution protection adjustment in the event the Company issues securities at an effective price less than the initial conversion price, subject to certain exceptions. If the Company’s stockholders do not approve the conversion feature of the Series B Preferred Stock, the shares of Series B Preferred Stock will not become convertible, and will remain outstanding in accordance with the terms of the Series B Designation of Rights.104 S. Michigan Avenue, Suite 500, Chicago, Illinois 60603.

Except as otherwise required by law, the holders of Series B Preferred Stock will have no right to vote on matters submitted to a vote of the Company’s stockholders. Without the prior written consent of 75% of the outstanding shares of Series B Preferred Stock, however, the Company may not: (a) alter or change adversely the powers, preferences or rights given to the Series B Preferred Stock or alter or amend the Series B Designation of Rights; (b) amend the Company’s certificate of incorporation or other charter documents in any manner that adversely affects any rights of the holders of Series B Preferred Stock; (c) increase the number of authorized shares of Series B Preferred Stock; or (d) enter into any agreement with respect to any of the foregoing.

In the event of the dissolution and winding up of the Company, the proceeds available for distribution to the Company’s stockholders shall be distributedpari passu among the holders of the shares of Common Stock and Series B Preferred Stock, pro rata based upon the number of shares held by each such holder, as if the outstanding shares of Series B Preferred Stock were convertible, and were converted, into shares of Common Stock.

DESCRIPTION OF WARRANTS

As explained above under “Selling Stockholders,” in connection with the Merger, the Company granted to the former stockholders of SafeOp the Merger Warrants, granted the Private Placement Warrants in connection with the Private Placement, and granted the New Warrants in connection with the Warrant Exercise Agreement. The Merger Warrants, Private Placement Warrants and New Warrants are sometimes referred to collectively herein as the “Warrants.” Each Warrant may be exercised for the purchase of one share of Common Stock for $3.50 per share (subject to adjustment in the event of a stock split, stock dividend, combination or other proportionate recapitalization). The Warrants may not be exercised until we have obtained Stockholder Approval. The Warrants are exercisable for cash for a term of five years from the date of Stockholder Approval. Unless a holder elects otherwise, the holder of a Warrant is restricted from the exercise of the Warrant or any portion thereof held by such holder, to the extent that, after giving effect to the exercise, such holder (together with such holder’s affiliates, and any persons acting as a group together with such holder or any of such holder’s affiliates) would beneficially own in excess of the Beneficial Ownership Limitation.

PLAN OF DISTRIBUTIONDISTRIBUTION

We are registering an aggregate of 36,129,060 shares of Common Stock heldSecurities Offered by or issuable to the Selling Stockholders identified in this prospectus pursuant to registration rights granted to the Selling Stockholders under certain agreements. We are also registering an indeterminate number of shares of Common Stock that may be issued in the future pursuant to provisions

Each of the Securities Purchase Agreement, Series B Designation of Rights, and the Warrants to prevent dilution resulting from stock splits, stock dividends, dilutive issuances, or similar transactions.

Each Selling Stockholder of the securitiesselling stockholders and any of itstheir pledgees, assignees andsuccessors-in-interest may, from time to time, sell any or all of the shares of common stock issuable upon exercise of their securitieswarrants covered hereby on Nasdaqthe principal trading market for our common stock or any other stock exchange, market or trading facility on which the securities are traded or in private transactions. These sales may be at fixed or negotiated prices. A Selling Stockholderselling stockholder may use any one or more of the following methods when selling securities:

acts as agent for the purchaser of securities, from the purchaser) in amounts to be negotiated, but, except as set forth in a supplement to this Prospectus,prospectus, in the case of an agency transaction not in excess of a customary brokerage commission in compliance with FINRA Rule 2440;2440; and in the case of a principal transaction a markup or markdown in compliance with FINRAIM-2440.

In connection with the sale of the securities or interests therein, the Selling Stockholdersselling stockholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of the securities in the course of hedging the positions they assume. The Selling Stockholdersselling stockholders may also sell securities short and deliver these securities to close out their short positions, or loan or pledge the securities to broker-dealers that in turn may sell these securities. The Selling Stockholdersselling stockholders may also enter into option or other transactions with broker-dealers or other financial institutions or create one or more derivative securities which require the delivery to such broker-dealer or other financial institution of securities offered by this prospectus, which securities such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).

The Selling Stockholdersselling stockholders and any broker-dealers or agents that are involved in selling the securities may be deemed to be “underwriters” within the meaning of the Securities Act in connection with such sales. In such event, any commissions received by such broker-dealers or agents and any profit on the resale of the securities purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. Each Selling Stockholderselling stockholders has informed the Companyus that it does not have any written or oral agreement or understanding, directly or indirectly, with any person to distribute the securities.

The Company isPursuant to the terms of a registration rights agreement, we are required to pay certain fees and expenses incurred by the Companywe incur incident to the registration of the securities. The Company hasWe have agreed to indemnify the Selling Stockholdersselling stockholders against certain losses, claims, damages and liabilities, including liabilities under the Securities Act. The Company is also required to pay certain fees and expenses in connection with any underwritten offering under the Registration Rights Agreement.

Selling Stockholders may be subject to the prospectus delivery requirements of the Securities Act including Rule 172 thereunder. In addition, any securities covered by this prospectus which qualify for sale pursuant to Rule 144 under the Securities Act may be sold under Rule 144 rather than under this prospectus. The Selling Stockholders have advised us that there is no underwriter or coordinating broker acting in connection with the proposed sale of the resale securities by the Selling Stockholders.

We agreed to keep this prospectus continuously effective until the earlier of(i) the date on which (i) with respect to the Selling Stockholders other thanL-5 Healthcare, the securities may be resold by such Selling Stockholdersthe selling stockholders without registration and without regard to any volume ormanner-of-sale limitations by reason of Rule 144, without the requirement for the Companyus to be in compliance with the current public information under Rule 144 under the Securities Act or any other rule of similar effect (ii) the securities have been previously sold in accordance with Rule 144 or any other rule of similar effect and new certificates for them not bearing a legend restricting transfer shall have been delivered by the Company or (iii)(ii) all of the securities have been sold pursuant to this prospectus.prospectus or Rule 144 under the Securities Act or any other rule of similar effect. The resale securities will be sold only through registered or licensed brokers or dealers if required under applicable state securities laws. In addition, in certain states, the resale securities covered hereby may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

Under applicable rules and regulations under the Exchange Act, any person engaged in the distribution of the resale securities may not simultaneously engage in market making activities with respect to the Common Stockcommon stock for the applicable restricted period, as defined in Regulation M, prior to the commencement of the distribution. In addition, the Selling Stockholdersselling stockholders will be subject to applicable provisions of the Exchange Act and the rules and regulations thereunder, including Regulation M, which may limit the timing of purchases and sales of the Common Stockcommon stock by the Selling Stockholdersselling stockholders or any other person. We will make copies of this

prospectus available to the Selling Stockholdersselling stockholders and have informed them of the need to deliver a copy of this prospectus to each purchaser at or prior to the time of the sale (including by compliance with Rule 172 under the Securities Act).

WeLEGAL MATTERS

The validity of our common stock offered hereby will bear all costs, expenses and fees in connection with the registration of the shares of Common Stock offered in this prospectus. The Selling Stockholders will bear any brokerage commissions and similar selling expenses that may result from their resale of the shares of Common Stock offered in this prospectus.

Some of the underwriters, dealers or agents used by the Selling Stockholders in any offering of securities under this prospectus may be customers of, engage in transactions with, and perform servicespassed upon for us and/or the Selling Stockholders, as applicable, or affiliates of ours and/or theirs, as applicable, in the ordinary course of business. Underwriters, dealers, agents and other persons may be entitled under agreements which may be entered into with us and/or the Selling Stockholders to indemnification against and contribution toward certain civil liabilities, including liabilities under the Securities Act, and to be reimbursed by us and/or such Selling Stockholders for certain expenses.

Any securities initially sold outside the United States may be resold in the United States through underwriters, dealers or otherwise.

Any underwriters to which offered securities are sold by the Selling Stockholders for public offering and sale may make a market in such securities, but those underwriters will not be obligated to do so and may discontinue any market making at any time.

To comply with the securities laws of some states, if applicable, the securities may be sold in jurisdictions only through registered or licensed brokers or dealers. In addition, in some states the securities may not be sold unless they have been registered or qualified for sale or an exemption from registration or qualification requirements is available and is complied with.

LEGAL MATTERS

Durham, Jones & Pinegar, P.C., Salt Lake City, Utah, will pass upon the validity of the issuance of the securities to be offered by this prospectus.St. George, Utah.

EXPERTS

Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements as of December 31, 2016, and for the year ended December 31, 2016 included in our Annual Report on Form 10-K for the year ended December 31, 2017, as set forth in their report, which is incorporated by reference in this prospectus and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young LLP’s report, given on their authority as experts in accounting and auditing.

Mayer Hoffman McCann P.C., independent registered public accounting firm, has audited our consolidated financial statements as of December 31, 2017, and for the year ended December 31, 2017 included in our Annual Report on Form 10-K as of and for the yearfiscal years ended December 31, 2017 and 2018, as set forth in their report dated March 29, 2019, which is incorporated by reference in this prospectus and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Mayer Hoffman McCann P.C.’s report, given on their authority as experts in accounting and auditing.

Nanavaty, Nanavaty & Davenport, LLP, independent public accounting firm,We have filed with the SEC a registration statement on Form S-3 under the Securities Act with respect to the shares of common stock being offered by this prospectus.  Certain information in the registration statement has auditedbeen omitted from this prospectus in accordance with the consolidated financial statementsrules and regulations of SafeOp Surgical, Inc. as ofthe SEC.  For further information with respect to the company and for the years ended December 31, 2017common stock offered by this prospectus, we refer you to the registration statement and 2016, as set forth in their reports, which are incorporated by referenceits exhibits.  Statements contained in this prospectus as to the contents of any contract or any other document referred to are not necessarily complete, and elsewhere in each instance, we refer you to the copy of the contract or other document filed as an exhibit to the registration statement.  Each of these statements is qualified in all respects by this reference.

We electronically file annual, quarterly and special reports, proxy and information statements and other information with the SEC. The SafeOp Surgical,SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC, including Alphatec Holdings, Inc. financial statements are incorporated by reference in reliance on Nanavaty, Nanavaty & Davenport, LLP’s reports, given on their authority as experts in accounting and auditing.

therewith; that indemnification provided for by Section 145 shall not be deemed exclusive of any other rights to which the indemnified party may be entitled;entitled; and the indemnification provided for by Section 145 shall, unless otherwise provided when authorized or ratified, continue as to a person who has ceased to be a director, officer, employee or agent and shall inure to the benefit of such person’s heirs, executors and administrators. Section 145 also empowers the 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, partnership, joint venture, trust or other enterprise against any liability asserted against such person and incurred by such person in any such capacity, or arising out of his status as such, whether or not the corporation would have the power to indemnify such person against such liabilities under Section 145.

Section 102(b)(7) of the DGCL provides that a corporation’s certificate of incorporation may contain a provision eliminating or limiting the personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, provided that such provision shall not eliminate or limit the liability of a director (i) for any breach of the director’s duty of loyalty to the corporation or its stockholders, (ii) for acts or omissions not in good faith or

which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL, or (iv) for any transaction from which the director derived an improper personal benefit.

The Company’s AmendedOur amended and Restated Certificaterestated certificate of Incorporation provideincorporation provides that the Companywe shall indemnify, to the fullest extent authorized by the DGCL, each person who is involved in any litigation or other proceeding because such person is or was our director or officer or is or was serving as an officer or director of another entity at our request, against all expense, loss or liability reasonably incurred or suffered in connection therewith.

The Company’s Bylaws Our amended and restated certificate of incorporation provides that the right to indemnification includes the right to be paid expenses incurred in defending any proceeding in advance of its final disposition, provided, however, that such advance payment will only be made upon delivery to us of an undertaking, by or on behalf of the director or officer, to repay all amounts so advanced if it is ultimately determined that such director is not entitled to indemnification. If we do not pay a proper claim for indemnification in full within 60 days after we receive a written claim for such indemnification, our amended and restated certificate of incorporation and our restatedby-laws authorize the claimant to bring an action against us and prescribe what constitutes a defense to such action.

As permitted by Section 145 of the DGCL, we carry insurance policies insuring our directors and officers against certain liabilities that they may incur in their capacity as directors and officers.

We have agreed toentered into indemnification agreements with all of our directors. The indemnification agreements require us to indemnify these individuals to the fullest extent permitted by Delaware law and to advance expenses incurred by them in connection with any proceeding against them with respect to which they may be entitled to indemnification by us.

The foregoing description is necessarily general and does not describe all details regarding the indemnification of officers, directors or controlling persons of the registrant.Item 16. Exhibits.

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(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement.

provided,however, that paragraphs (1)(i), (ii), and (iii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to sectionSection 13 or sectionSection 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initialbona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(A) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(B) 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)(1)(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 described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which the prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(5) That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the  The undersigned registrant hereby undertakes that, in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

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(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(6) That, for purposes of determining any liability under the Securities Act, of 1933, each filing of registrant’sthe registrant's annual report pursuant to Sectionsection 13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’splan's annual report pursuant to Sectionsection 15(d) of the Securities Exchange Act of 1934)Act) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initialbona fide offering thereof.

(7) (c) Insofar as indemnification for liabilities arising under the SecuritiesSecurities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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EXHIBIT INDEX

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 FormS-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized in the City of Carlsbad, State of California, on May 1, 2018.July 16, 2019.

POWER OF ATTORNEY

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. Each person whose signature appears below authorizes Patrick S. Miles and Jeffrey G. Black, and each or any of them with full power of substitution and resubstitution, his true and lawful attorney-in-fact, for him in any and all capacities, to sign any amendments (including post-effective amendments or supplements) to this registration statement and to file the same, with exhibits thereto, and other documents in connection therewith, with the SEC.