SEC Form S-8 filed by I-MAB

As filed with the Securities and Exchange Commission on September 11, 2025

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

I-Mab

(Exact name of registrant as specified in its charter)

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. ¨

The Registration Statement shall become effective upon filing in accordance with Rule 462 under the Securities Act.

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1. Plan Information*

Item 2. Registrant Information and Employee Plan Annual Information*

*Information required by Part I to be contained in the Section 10(a) prospectus is omitted from this registration statement on Form S-8 (this “Registration Statement”) in accordance with Rule 428 under the Securities Act of 1933, as amended (the “Securities Act”) and the “Note” to Part I of Form S-8. The documents containing the information specified in this Part I of Form S-8 will be separately provided to the participants in the Registrant’s 2025 Omnibus Share Incentive Plan and 2025 Share Incentive Scheme covered by this Registration Statement, as specified by the U.S. Securities and Exchange Commission (the “SEC” or the “Commission”) pursuant to Rule 428(b)(1) under the Securities Act. Such documents are not required to be, and are not, filed with the Commission either as part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule 424 of the Securities Act. These documents and the documents incorporated by reference in this Registration Statement pursuant to Item 3 of Part II hereof, taken together, constitute a prospectus that meets the requirements of Section 10(a) of the Securities Act.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference.

The following documents have been filed by the Registrant with the Commission and are incorporated herein by reference:

In addition, all documents filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (excluding any portions thereof furnished by the Registrant, including but not limited to any certification required by 18 U.S.C. § 1350), on or after the date of this Registration Statement, prior to the filing of a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of filing of such documents. For purposes of this Registration Statement, any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

Item 4. Description of Securities.

Not applicable.

Item 5. Interests of Named Experts and Counsel.

Not applicable.

Item 6. Indemnification of Directors and Officers.

Cayman Islands law does not limit the extent to which a company’s articles of association may provide for indemnification of directors and officers, except to the extent any such provision may be held by the Cayman Islands courts to be contrary to public policy, such as to provide indemnification against civil fraud or the consequences of committing a crime. The Registrant’s Sixth Amended and Restated Memorandum and Articles of Association, adopted by its shareholders on October 29, 2019, provides that the Registrant shall indemnify each of its directors and officers against all actions, proceedings, costs, charges, expenses, losses, damages or liabilities incurred or sustained by such director or officer, other than by reason of such person’s own dishonesty, willful default or fraud, in or about the conduct of the Registrant’s business or affairs (including as a result of any mistake of judgment) or in the execution or discharge of his or her duties, powers, authorities or discretions, including without prejudice to the generality of the foregoing, any costs, expenses, losses or liabilities incurred by such director or officer in defending (whether successfully or otherwise) any civil proceedings concerning the Registrant or its affairs in any court whether in the Cayman Islands or elsewhere.

Pursuant to the indemnification agreements, the form of which was filed as Exhibit 10.3 to the Registrant’s registration statement on Form F-1, as amended (File No. 333-234363), the Registrant has agreed to indemnify its directors and officers to the fullest extent permitted by law against certain liabilities and expenses incurred by such persons in connection with claims made by reason of their being such a director or officer.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers or persons controlling the Registrant pursuant to the foregoing provisions, the Registrant has been informed that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

The Registrant also maintains a directors and officers liability insurance policy for its directors and officers.

Item 7. Exemption from Registration Claimed.

Not Applicable.

Item 8. Exhibits.

* Filed herewith.

+ Indicates management contract or compensatory plan or arrangement

Item 9. Undertakings.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8, and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized in the City of Rockville, State of Maryland, on the 11th day of September, 2025.

I-Mab

/s/ Joseph Skelton

Name: Joseph Skelton

Title: Chief Financial Officer

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each of the undersigned constitutes and appoints each of Joseph Skelton and Sean Fu, and each of them, his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement on Form S-8 and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto each of said attorneys-in-fact and agents, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully for all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that each of said attorneys-in-facts and agents, or his or her substitutes or resubstitutes, or any of them, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed below by the following persons in the capacities and on the dates indicated.

SIGNATURE OF AUTHORIZED U.S. REPRESENTATIVE OF THE REGISTRANT

Pursuant to the requirements of the Securities Act of 1933, as amended, the undersigned, the duly authorized representative in the United States of I-Mab, has signed this Registration Statement on Form S-8 in Rockville, Maryland on September 11, 2025.

I-Mab Biopharma US Ltd.

Authorized U.S. Representative

/s/ Joseph Skelton

Name: Joseph Skelton

Title: Chief Financial Officer