IMGO Imago BioSciences Inc

As filed with the Securities and Exchange Commission on January 11, 2023

Registration No. 333-266963

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1

TO

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

IMAGO BIOSCIENCES, INC.

(Exact name of registrant as specified in its charter)

303 Twin Dolphin Drive, 6th Floor

Redwood City, California 94065

(415) 529-5055

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Kelly E.W. Grez, Secretary

Imago BioSciences, Inc.

303 Twin Dolphin Drive, 6th Floor

Redwood City, California 94065

(415) 529-5055

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

Copy to:

Saee Muzumdar

Gibson, Dunn & Crutcher LLP

200 Park Avenue

New York, NY 10166-0193

(212) 351-4035

Approximate date of commencement of proposed sale to the public: Not Applicable. Removal from registration of securities that were not sold pursuant to the above referenced registration 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:  ☐

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:  ☐

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, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange 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) of the Securities Act.  ☐

TERMINATION OF REGISTRATION

This Post-Effective Amendment No. 1 relates to the following Registration Statement on Form S-3 (the “Registration Statement”) filed by Imago BioSciences, Inc. (the “Company”) with the Securities and Exchange Commission:

Pursuant to the Agreement and Plan of Merger, dated as of November 19, 2022 (the “Merger Agreement”), by and among the Company, Merck Sharp & Dohme LLC, a New Jersey limited liability company (“Parent”) and M-Inspire Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Parent (“Merger Sub”), Merger Sub merged with and into the Company, with the Company continuing as the surviving corporation and a direct wholly owned subsidiary of Parent. As a result of the transactions contemplated by the Merger Agreement, the Company has terminated all offerings of its securities pursuant to the Registration Statement and hereby removes and withdraws from registration all securities registered pursuant to the Registration Statement that remain unsold as of the date hereof. The Registration Statement is hereby amended, as appropriate, to reflect the deregistration of such securities.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Post-Effective Amendment No. 1 to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Rahway, in the State of New Jersey, on this 11th day of January, 2023.

Pursuant to the Rule 478 of the Securities Act of 1933, as amended, no other person is required to sign this Post-Effective Amendment No. 1 to Registration Statement.

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