Form 15-12G - Securities registration termination [Section 12(g)]

---

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 15

CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934.

001-40869

Commission File Number

THESEUS PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

314 Main Street Cambridge, Massachusetts 02142 [phone]

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

Common Stock, $0.0001 par value per share

(Title of each class of securities covered by this Form)

None

(Titles of all other classes of securities for which a duty to file reports under section 13(a) or 15(d) remains)

Please place an X in the box(es) to designate the appropriate rule provision(s) relied upon to terminate or suspend the duty to file reports:

Rule 12g-4(a)(1)

☒

Rule 12g-4(a)(2)

☐

Rule 12h-3(b)(1)(i)

☒

Rule 12h-3(b)(1)(ii) Rule 15d-6

☐

Rule 15d-22(b)

☐

Approximate number of holders of record as of the certification or notice date:

One

Pursuant to the requirements of the Securities Exchange Act of 1934, Theseus Pharmaceuticals, Inc. has caused this certification/notice to be signed on its behalf by the undersigned duly authorized person.

Date: February 26, 2024	THESEUS PHARMACEUTICALS, INC.
	By:	/s/ Michael Hearne
		Name: Michael Hearne
		Title: Chief Financial Officer

---

---