UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(D)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): April 30, 2018

IMPAX LABORATORIES, INC.

(Exact name of registrant as specified in its charter)

(510) 240-6000

Registrant’s telephone number, including area code

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company  ☐

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 13(a) of the Exchange Act.  ☐

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On April 27, 2018, Impax Laboratories, Inc. (the “Company”) and Amneal Pharmaceuticals LLC (“Amneal”) issued a joint press release announcing that they had received all regulatory approvals required in connection with the previously announced business combination of the Company and Amneal (the “Business Combination”), and that the parties expect to consummate the Business Combination on May 4, 2018. A copy of the press release is attached to this report as Exhibit 99.1 and incorporated by reference herein.

Forward-Looking Statements

This communication includes “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements are based on our beliefs and assumptions. These forward-looking statements are identified by terms and phrases such as: anticipate, believe, intend, estimate, expect, continue, should, could, may, plan, project, predict, will, target, potential, forecast, and the negative thereof and similar expressions. Forward-looking statements by their nature address matters that are, to different degrees, uncertain, such as statements about the potential timing or consummation of the proposed transaction or the anticipated benefits thereof, including, without limitation, future financial and operating results. Impax cautions readers that these and other forward-looking statements are not guarantees of future results and are subject to risks, uncertainties and assumptions that could cause actual results to differ materially from those expressed in any forward-looking statements. Important risk factors that could cause actual results to differ materially from those indicated in any forward-looking statement include, but are not limited to: (i) the risk that a condition to effecting the transaction contemplated by the Business Combination Agreement dated as of October 17, 2017, by and among Impax Laboratories, Inc. (“Impax”), Amneal Pharmaceuticals LLC (“Amneal”), Atlas Holdings, Inc. (“Holdco”), and K2 Merger Sub Corporation, as amended by Amendment No. 1, dated as of November 21, 2017, and Amendment No. 2, dated as of December 16, 2017, may not be satisfied; (ii) the ability of Impax and Amneal to integrate their businesses successfully and to achieve anticipated synergies, (iii) the possibility that other anticipated benefits of the proposed transaction will not be realized, including without limitation, anticipated revenues, expenses, earnings and other financial results, and growth and expansion of the new combined company’s operations, and the anticipated tax treatment, (iv) potential litigation relating to the proposed transaction that could be instituted against Impax, Amneal or their respective directors, (v) possible disruptions from the proposed transaction that could harm Impax’s and/or Amneal’s business, including current plans and operations, (vi) the ability of Impax or Amneal to retain, attract and hire key personnel, (vii) potential adverse reactions or changes to relationships with clients, employees, suppliers or other parties resulting from the announcement or completion of the transaction, (viii) potential business uncertainty, including changes to existing business relationships, during the pendency of the business combination that could affect Impax’s or Amneal’s financial performance, (ix) certain restrictions during the pendency of the transaction that may impact Impax’s or Amneal’s ability to pursue certain business opportunities or strategic transactions, (x) continued availability of capital and financing and rating agency actions, (xi) legislative, regulatory and economic developments; (xii) unpredictability and severity of catastrophic events, including, but not limited to, acts of terrorism or outbreak of war or hostilities, as well as management’s response to any of the aforementioned factors; and (xiii) such other factors as are set forth in Impax’s periodic public filings with the Securities and Exchange Commission (the “SEC”), including but not limited to those described under the headings “Risk

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Factors” and “Cautionary Statement Regarding Forward-Looking Information” in Impax’s Form 10-K for the fiscal year ended December 31, 2017, in the Form S-4 filed by Holdco, in the definitive proxy statement on Schedule 14A filed by Impax and in Impax’s other filings made with the SEC from time to time, which are available via the SEC’s website at www.sec.gov. While the list of factors presented here is, and the list of factors to be presented in the proxy statement are, considered representative, no such list should be considered to be a complete statement of all potential risks and uncertainties. Unlisted factors may present significant additional obstacles to the realization of forward looking statements. Consequences of material differences in results as compared with those anticipated in the forward-looking statements could include, among other things, business disruption, operational problems, financial loss, legal liability to third parties and similar risks, any of which could have a material adverse effect on Impax’s or Amneal’s consolidated financial condition, results of operations, credit rating or liquidity. In light of these risks, uncertainties and assumptions, the events described in the forward-looking statements might not occur or might occur to a different extent or at a different time than Impax has described. All such factors are difficult to predict and beyond our control. All forward-looking statements included in this document are based upon information available to Impax on the date hereof, and unless legally required, Impax disclaims and does not undertake any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

(d) Exhibits

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: April 30, 2018