Apellis Pharmaceuticals, Inc.

false 0001492422 --12-31 0001492422 2026-05-14 2026-05-14 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): May 14, 2026 Apellis Pharmaceuticals, Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-38276 27-1537290 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IRS Employer Identification No.) 100 Fifth Avenue Waltham , MA 02451 (Address of Principal Executive Offices) (Zip Code) Registrant’s telephone number, including area code: (617) 977-5700 Not applicable (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): ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act: Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share APLS Nasdaq Global Select Market 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. ☐ Introductory Note As previously disclosed, on March 31, 2026, Apellis Pharmaceuticals, Inc., a Delaware corporation (the “Company”), entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Biogen Inc., a Delaware corporation (“Biogen”), and Aspen Purchaser Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Biogen (“Purchaser”). Pursuant to the Merger Agreement, on April 14, 2026, Purchaser commenced a tender offer (the “Offer”) to acquire any and all of the issued and outstanding shares of common stock, par value $0.0001 per share, of the Company (the “Shares”) in exchange for (i) $41.00 per Share, net to the seller in cash, without interest and subject to reduction for any applicable tax withholding (the “Cash Amount”), plus (ii) one contractual, non-transferable contingent value right per Share (each, a “CVR”), representing the right to receive potential payments of up to an aggregate of $4.00 in cash, without interest and subject to reduction for any applicable tax withholding, upon the achievement of certain specified milestones in accordance with the terms and conditions of that certain Contingent Value Rights Agreement, dated as of May 14, 2026 (the “CVR Agreement”), by and among Biogen, the Company and Equiniti Trust Company LLC (“Equiniti,” and the Cash Amount plus one CVR, collectively, the “Offer Price”). The Offer and related withdrawal rights expired as scheduled at one minute after 11:59 p.m., Eastern Time, on May 13, 2026 (such date and time, the “Expiration Time”), and was not extended. Equiniti, the depositary for the Offer, advised Purchaser that, immediately prior to the Expiration Time, a total of 105,687,831 Shares were validly tendered (and not validly withdrawn) pursuant to the Offer, representing approximately 82.4% of the Shares outstanding immediately prior to the Expiration Time. The number of Shares validly tendered (and not validly withdrawn) pursuant to the Offer (excluding Shares tendered pursuant to guaranteed delivery procedures that have not yet been “received”, as such term is defined by Section 251(h)(6)(f) of the General Corporation Law of the State of Delaware (the “DGCL”)), together with any Shares beneficially owned by Biogen or any of its subsidiaries, satisfied the Minimum Condition (as defined in the Merger Agreement). All other conditions to the consummation of the Offer having been satisfied or waived, on May 14, 2026, Purchaser irrevocably accepted for payment all Shares that were validly tendered (and not validly withdrawn) pursuant to the Offer, and payment for such Shares will be made promptly in accordance with the terms of the Offer and the Merger Agreement. Following the completion of the Offer, the remaining conditions to the Merger (as defined below) set forth in the Merger Agreement were satisfied or waived, and on May 14, 2026, pursuant to the terms of the Merger Agreement, Purchaser merged with and into the Company, without a vote of the stockholders of the Company in accordance with Section 251(h) of the DGCL, with the Company continuing as the surviving corporation of the Merger (the “Surviving Corporation”) and as a wholly owned subsidiary of Biogen (the “Merger”, and the date and time at which the Merger became effective, the “Effective Time”). Pursuant to the Merger Agreement, at the Effective Time, each Share (other than Shares that were (i) held in the treasury of the Company, (ii) irrevocably accepted for purchase in the Offer by Purchaser and “received” (as such term is defined by Section 251(h)(6)(f) of the DGCL) by Purchaser, (iii) held by Biogen, Purchaser or any other wholly owned subsidiary of Biogen as of both the commencement of the Offer and immediately prior to the Effective Time and (iv) held by stockholders who were entitled to, and properly demanded, appraisal for such Shares in accordance with Section 262 of the DGCL) was cancelled and converted into the right to receive the Offer Price without interest, subject to reduction for any applicable withholding taxes (the “Merger Consideration”). Pursuant to the terms of the Merger Agreement, effective as of immediately prior to the Effective Time, any outstanding and unexercised warrant to purchase Shares (each, a “Company Warrant”) was deemed to be exercised in full in a “cashless exercise” pursuant to its terms, and any Shares issued upon such deemed cashless exercise were automatically converted into the right to receive the Merger Consideration, without interest and subject to applicable withholding taxes. As of immediately prior to the Effective Time, no Company Warrants were outstanding. At the Effective Time, subject to all required withholding taxes and with each CVR payable in accordance with the CVR Agreement, each outstanding equity award of the Company was treated as follows: (i) each option to purchase Shares (each, a “Company Option”) that had vested as of immediately prior to the Expiration Time (including any Company Option that vested as a result of the transactions) with an exercise price less than the Cash Amount was automatically cancelled and converted into the right to receive from the Surviving Corporation a cash payment equal to the product of the total number of Shares underlying such vested Company Option multiplied by the excess of the Cash Amount over the exercise price per Share of such vested Company Option, plus one CVR per Share underlying such vested Company Option; (ii) each vested Company Option with an exercise price equal to or greater than the Cash Amount but less than the Aggregate Amount (as defined in the Merger Agreement) was cancelled and converted into the right to receive one CVR per Share underlying such vested Company Option (with any Milestone Payment (as defined below) reduced by the excess, if any, of the applicable exercise price per Share over the Cash Amount, as set forth in the CVR Agreement); (iii) each Comp