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): December 14, 2023

PFIZER INC.

(Exact name of registrant as specified in its charter)

(Address of principal executive offices)

Registrant’s telephone number, including area code:

(212) 733-2323

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 obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Securities registered pursuant to Section 12(b) of the Act:

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.  ☐

Pursuant to an Agreement and Plan of Merger (the “Merger Agreement”), dated as of March 12, 2023, by and among Pfizer Inc., a Delaware corporation (“Pfizer”), Aris Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Pfizer (“Merger Sub”), and Seagen Inc., a Delaware corporation (“Seagen”), Merger Sub was merged with and into Seagen (the “Merger”), with Seagen surviving the Merger as a wholly owned subsidiary of Pfizer. The Merger became effective on December 14, 2023 (the “Effective Time”).

At the Effective Time, each issued and outstanding share of Seagen common stock, par value $0.001 per share (the “Seagen Shares”), was converted into the right to receive (without interest) $229.00 in cash (the “Merger Consideration”), subject to limited exceptions set forth in the Merger Agreement, and each outstanding Seagen equity award was either converted into the right to receive the Merger Consideration for each share of Seagen common stock underlying such awards (based on the achievement of any applicable performance metrics as set forth in the Merger Agreement), less applicable tax withholdings, or converted into a Pfizer cash-based award otherwise remaining subject to substantially the same terms and conditions applicable to such Seagen equity award immediately prior to the effective time of the Merger, in each case subject to the terms and conditions of the Merger Agreement.

The foregoing description of the Merger Agreement and the transactions contemplated thereby does not purport to be complete and is qualified in its entirety by reference to the Merger Agreement, a copy of which was filed as Exhibit 2.1 to Pfizer’s Current Report on Form 8-K filed with the U.S. Securities and Exchange Commission on March 13, 2023, and is incorporated by reference into this Item 2.01.

On December 14, 2023, Pfizer issued a press release announcing the successful completion of the Merger. A copy of the press release is furnished as Exhibit 99.1 hereto and is incorporated by reference into this Item 7.01.

The information contained in this Item 7.01 and Exhibit 99.1 hereto shall not be deemed to be “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of such section, nor will such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as may be expressly set forth by specific reference in such filing.

(d) Exhibits.

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.