Biogen to merge Apellis (NASDAQ: APLS) after tender offer closes

Rhea-AI Filing Summary

Biogen's wholly owned purchaser accepted for payment 105,687,831 Shares tendered in the offer for Apellis, representing approximately 82.4% of Shares outstanding immediately prior to the offer's expiration. The offer provided $41.00 per Share in cash plus one contingent value right per Share for up to $4.00 in additional cash upon specified milestones. All conditions to closing were satisfied or waived and, pursuant to the Merger Agreement and Section 251(h) of the DGCL, Purchaser will merge with and into Apellis and the merger will be consummated on May 14, 2026. At the Effective Time, each outstanding Share (subject to limited exceptions) will be converted into the right to receive the Merger Consideration, the Shares will be delisted from Nasdaq, and Apellis will become a wholly owned subsidiary of Biogen.

Insights

M&A Attorney

Deal mechanics complete; closing invoked under DGCL Section 251(h).

The purchaser accepted 105,687,831 Shares tendered (about 82.4% outstanding) and will effect the merger on May 14, 2026 under Section 251(h) of the DGCL, permitting a short-form merger without a stockholder vote.

Key dependencies: the conversion of outstanding shares into the cash consideration and CVRs, limited exceptions for treasury, previously "received" tendered shares, Biogen-owned shares, and any properly demanded appraisal rights under Section 262. Subsequent filings will reflect delisting and termination of Exchange Act registration.

Corporate Finance Analyst

Transaction delivers defined cash plus contingent upside via CVRs.

The consideration is $41.00 cash per Share plus one CVR per Share for up to $4.00 upon milestone achievement; payment for accepted Shares will be made promptly following acceptance.

Material items to watch in post-close filings include aggregate CVR treatment and any appraisal proceedings under Section 262 that could affect timing or cash outflows. Cash flow treatment at closing is described as cash to selling holders; CVR payouts depend on future milestones.

Key Figures

Offer price: $41.00 per Share Contingent value right: $4.00 aggregate per Share Shares validly tendered: 105,687,831 Shares +2 more

5 metrics

Offer price $41.00 per Share Offer to Purchase dated April 14, 2026

Contingent value right $4.00 aggregate per Share CVR representing up to $4.00 in contingent cash payments

Shares validly tendered 105,687,831 Shares Validly tendered and not validly withdrawn as of Expiration Time

Tender percentage 82.4% Approximate percent of Shares outstanding immediately prior to Expiration Time

Merger consummation date May 14, 2026 Effective Time / scheduled merger date under Merger Agreement

Key Terms

contingent value right (CVR), Section 251(h) of the DGCL, appraisal under Section 262

3 terms

contingent value right (CVR) financial

"one contractual, non-transferable contingent value right per Share representing the right to receive contingent cash payments"

A contingent value right (CVR) is a short-term claim given to shareholders as part of a corporate deal that pays out only if specific future milestones or targets are met, such as regulatory approval or sales thresholds. Think of it like a coupon that becomes redeemable only if the company clears a stated hurdle; it matters to investors because it preserves potential upside from uncertain outcomes while also carrying extra risk and separate market value from the main stock.

Section 251(h) of the DGCL regulatory

"will consummate the Merger on May 14, 2026 in accordance with Section 251(h) of the DGCL"

appraisal under Section 262 regulatory

"stockholders who were entitled to, and properly demanded, appraisal for such Shares in accordance with Section 262 of the DGCL"

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE TO

(Amendment No. 3)

Tender Offer Statement Pursuant to Section 14(d)(1) or 13(e)(1)

of the Securities Exchange Act of 1934

APELLIS PHARMACEUTICALS, INC.

(Name of Subject Company)

ASPEN PURCHASER SUB, INC.

(Offeror)

A Wholly Owned Subsidiary of

BIOGEN INC.

(Parent of Offeror)

(Names of Filing Persons (identifying status as offeror, issuer or other person))

COMMON STOCK, PAR VALUE $0.0001 PER SHARE

(Title of Class of Securities)

03753U106

(CUSIP Number of Class of Securities)

Wendell Taylor

Chief Corporation Counsel

Biogen Inc.

225 Binney Street

Cambridge, MA 02142

(617) 679-2000

(Name, address and telephone number of person authorized to receive notices and communications on behalf of filing persons)

with copies to:

Aaron M. Gruber

Bethany A. Pfalzgraf

Ryan J. Wichtowski

Cravath, Swaine & Moore LLP

Two Manhattan West

375 Ninth Avenue

New York, NY 10001

(212) 474-1000

☐ Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

☒ third-party tender offer subject to Rule 14d-1.

☐ issuer tender offer subject to Rule 13e-4.

☐ going-private transaction subject to Rule 13e-3.

☐ amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: ☒

If applicable, check the appropriate box(es) below to designate the appropriate rule provision(s) relied upon:

☐ Rule 13e-4(i) (Cross-Border Issuer Tender Offer)

☐ Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)

This Amendment No. 3 (this “Amendment”) amends and supplements the Tender Offer Statement on Schedule TO (as amended and together with any subsequent amendments and supplements thereto, the “Schedule TO”), filed with the U.S. Securities and Exchange Commission (“SEC”) on April 14, 2026, by Biogen Inc., a Delaware corporation (“Biogen”). The Schedule TO relates to the tender offer by Aspen Purchaser Sub, Inc., a Delaware corporation and a wholly owned indirect subsidiary of Biogen (“Purchaser”), for all of the outstanding shares of common stock, par value $0.0001 per share (the “Shares”), of Apellis Pharmaceuticals, Inc., a Delaware corporation (“Apellis”), 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, plus (ii) one contractual, non-transferable contingent value right per Share representing the right to receive contingent cash 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 the CVR Agreement (as defined in the Offer to Purchase), in each case, upon the terms and subject to the conditions set forth in the Offer to Purchase dated April 14, 2026 (together with any amendments and supplements thereto, the “Offer to Purchase”) and in the related Letter of Transmittal, copies of which were filed as Exhibit (a)(1)(A) and Exhibit (a)(1)(B), respectively, to the Schedule TO.

Except to the extent specifically provided in this Amendment, the information set forth in the Schedule TO remains unchanged. This Amendment is being filed to reflect certain updates as reflected below. Capitalized terms used but not defined herein have the respective meanings ascribed to them in the Schedule TO.

Items 1 through 9 and 11

The Offer to Purchase and Items 1 through 9 and Item 11 of the Schedule TO, to the extent such Items incorporate by reference the information contained in the Offer to Purchase, are hereby amended and supplemented as follows:

“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 the Offer was not extended. Equiniti Trust Company, LLC, 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.

As of 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 DGCL), together with any Shares beneficially owned by Biogen or any of its subsidiaries, satisfied the Minimum Condition. 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 Expiration Time and acceptance for payment of the Shares, the remaining conditions to the Merger set forth in the Merger Agreement were satisfied or waived, and Purchaser will consummate the Merger on May 14, 2026 in accordance with Section 251(h) of the DGCL without a vote of the stockholders of Apellis. At the Effective Time, Purchaser will merge with and into Apellis, the separate existence of Purchaser will cease and Apellis will continue as the surviving corporation in the Merger and a wholly owned subsidiary of Biogen. Pursuant to the Merger Agreement, at the Effective Time, each Share issued and outstanding immediately prior to the effective time (other than Shares that are (i) held in the treasury of Apellis, (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 or (iv) held by stockholders who were entitled to, and properly demanded, appraisal for such Shares in accordance with Section 262 of the DGCL) will be converted into the right to receive the Merger Consideration without interest and subject to reduction for any applicable withholding taxes.

As a result of the Merger, the Shares will be delisted and will cease to trade on the Nasdaq Global Select Market. Biogen and Apellis intend to take steps to cause the termination of the registration of the Shares under the Exchange Act and suspend all of Apellis’ reporting obligations under the Exchange Act as promptly as practicable.”

SIGNATURES

After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

BIOGEN INC.
By		/s/ Robin Kramer
		Name: Robin Kramer
		Title: Chief Financial Officer
		Date: May 14, 2026

ASPEN PURCHASER SUB, INC.
By		/s/ Michael Dambach
		Name: Michael Dambach
		Title: Authorized Signatory
		Date: May 14, 2026

FAQ

What consideration did Biogen offer for Apellis (APLS)?

Biogen offered $41.00 per Share in cash plus one CVR per Share for up to $4.00 in contingent cash payments upon specified milestones, as set forth in the Offer to Purchase.

How many Apellis shares were validly tendered into the offer?

A total of 105,687,831 Shares were validly tendered (and not validly withdrawn), representing approximately 82.4% of Shares outstanding immediately prior to the Expiration Time.

When will the merger between Biogen and Apellis be consummated?

The Purchaser accepted tendered shares and the Merger is scheduled to be consummated on May 14, 2026 under Section 251(h) of the DGCL, resulting in Apellis becoming a wholly owned subsidiary of Biogen.

What happens to Apellis shares at the Effective Time?

At the Effective Time, each outstanding Share (subject to specific exceptions) will be converted into the right to receive the Merger Consideration; the Shares will be delisted from Nasdaq and Apellis will continue as a Biogen subsidiary.

Will Apellis remain a reporting company after the merger?

Biogen and Apellis intend to take steps to terminate the registration of the Shares under the Exchange Act and suspend Apellis' reporting obligations as promptly as practicable following the merger.