Century Therapeutics (IPSC) CEO reports 463-share tax withholding on RSU vesting

Rhea-AI Filing Summary

Century Therapeutics, Inc. President and CEO Brent Pfeiffenberger reported a tax-related share disposition. On the vesting of restricted stock units, 463 shares of common stock were withheld by the company at $2.56 per share to satisfy tax withholding obligations. This was not an open-market sale. After this withholding, he directly holds 3,766,355 shares of Century Therapeutics common stock.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Pfeiffenberger Brent

Role President and CEO

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	463	$2.56	$1K

Holdings After Transaction: Common Stock — 3,766,355 shares (Direct)

Footnotes (1)

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Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Pfeiffenberger Brent

(Last) (First) (Middle)

C/O CENTURY THERAPEUTICS, INC.

25 N 38TH STREET, 11TH FLOOR

(Street)

PHILADELPHIA PA 19104

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Century Therapeutics, Inc. [ IPSC ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President and CEO

3. Date of Earliest Transaction (Month/Day/Year)
03/06/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	03/06/2026		F(1)		463	D	$2.56	3,766,355	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Represents shares withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting of restricted stock units.

	/s/ Douglas Carr, Attorney-in-Fact	03/10/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did Century Therapeutics (IPSC) report for its CEO?

Century Therapeutics reported that President and CEO Brent Pfeiffenberger had 463 common shares withheld to cover tax obligations upon RSU vesting. This Form 4 event reflects administrative tax withholding, not an open-market stock sale or purchase.

Was the IPSC CEO’s Form 4 transaction a sale of shares on the open market?

No, the transaction was not an open-market sale. The 463 Century Therapeutics shares were withheld by the company to satisfy tax withholding obligations triggered by restricted stock unit vesting, a routine administrative step rather than a discretionary sale.

How many Century Therapeutics (IPSC) shares were involved in the CEO’s tax withholding?

The filing shows that 463 shares of Century Therapeutics common stock were withheld at $2.56 per share. These shares were used to satisfy tax withholding obligations arising from the vesting of restricted stock units awarded to the CEO.

How many Century Therapeutics (IPSC) shares does the CEO hold after this Form 4 transaction?

Following the tax-withholding disposition, Brent Pfeiffenberger directly holds 3,766,355 Century Therapeutics common shares. The withheld 463 shares modestly reduced his position as part of RSU-related tax settlement, not through an open-market sale transaction.

What does the F transaction code mean in the IPSC CEO’s Form 4?

The F code indicates shares were disposed of to pay an exercise price or tax liability. For Century Therapeutics, 463 CEO shares were withheld by the issuer to satisfy RSU-related tax obligations, classifying this event as tax withholding rather than a typical market sale.