Centessa (NASDAQ: CNTA) CPO exercises options and sells 41,076 shares

Rhea-AI Filing Summary

Centessa Pharmaceuticals Chief People Officer Karen M. Anderson exercised options and sold shares in a planned transaction. She exercised options to acquire 41,076 Ordinary Shares at an exercise price of $8.01 per share, then sold 41,076 Ordinary Shares in open‑market trades at a weighted average price of $30.1242 per share, with individual sale prices ranging from $29.99 to $30.44. The sale was carried out under a pre‑arranged Rule 10b5‑1 trading plan adopted on November 12, 2025. After these transactions, Anderson directly holds 62,085 Ordinary Shares, which may be represented by American Depositary Shares on a one‑for‑one basis.

Insights

Equity compensation analyst

Routine option exercise and sale under a 10b5‑1 plan.

Chief People Officer Karen M. Anderson exercised options for 41,076 Ordinary Shares at $8.01 and sold the same number of shares at a weighted average of $30.1242. This is a classic exercise‑and‑sell pattern.

The filing notes the sales occurred under a pre‑arranged Rule 10b5‑1 trading plan adopted on November 12, 2025, indicating the timing was scheduled in advance rather than opportunistic. Following the sale, she still directly holds 62,085 Ordinary Shares, suggesting she retains a meaningful equity stake.

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).

X

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^*

Anderson Karen M.

(Last) (First) (Middle)

C/O CENTESSA PHARMACEUTICALS PLC

3RD FL., 1 ASHLEY RD, ALTRINCHAM

(Street)

CHESHIRE WA14 2DT

(City) (State) (Zip)

UNITED KINGDOM

(Country)

2. Issuer Name and Ticker or Trading Symbol
Centessa Pharmaceuticals plc [ CNTA ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief People Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/26/2026

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

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

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

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
Ordinary Shares(1)	03/26/2026		M		41,076	A	$8.01	103,161	D
Ordinary Shares(1)	03/26/2026		S(2)		41,076	D	$30.1242(3)	62,085	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
Share Option (right to buy)	$8.01	03/26/2026		M			41,076	(4)	02/01/2034	Ordinary Shares(1)	41,076	$0	83,924	D

Explanation of Responses:

1. The Ordinary Shares may be represented by American Depositary Shares, each of which currently represents one Ordinary Share.

2. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 12, 2025.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $29.99 to $30.44, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

4. 1/48th of the shares subject to such option shall vest and become exercisable in equal monthly installments with the first installment vesting on March 1, 2024.

Remarks:

	/s/ Raphael Deferiere, attorney-in-fact	03/27/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transactions did Centessa (CNTA) report for Karen M. Anderson?

Centessa reported that Chief People Officer Karen M. Anderson exercised options for 41,076 Ordinary Shares at $8.01 per share and sold 41,076 Ordinary Shares in open‑market transactions at a weighted average price of $30.1242 per share.

Was the Centessa (CNTA) insider stock sale made under a 10b5-1 plan?

Yes. The filing states the sales were effected under a Rule 10b5‑1 trading plan adopted by Karen M. Anderson on November 12, 2025. Such plans pre‑schedule trades, suggesting the timing of these sales was pre‑arranged rather than discretionary.

How many Centessa (CNTA) shares does Karen M. Anderson hold after the transactions?

After the reported transactions, Karen M. Anderson directly holds 62,085 Ordinary Shares of Centessa Pharmaceuticals. The filing also notes that each Ordinary Share may be represented by one American Depositary Share, maintaining a one‑for‑one relationship.

What prices were realized in the Centessa (CNTA) insider share sales?

The weighted average sale price for the 41,076 Ordinary Shares sold was $30.1242 per share. The filing explains that individual trades occurred in a range from $29.99 to $30.44, and detailed breakdowns are available upon request.

What type of derivative security did Karen M. Anderson exercise at Centessa (CNTA)?

She exercised a Share Option (right to buy) covering 41,076 Ordinary Shares at an exercise price of $8.01 per share. A footnote explains that one forty‑eighth of the option vests monthly starting on March 1, 2024.

How are Centessa (CNTA) Ordinary Shares related to its American Depositary Shares?

The filing notes that Centessa’s Ordinary Shares may be represented by American Depositary Shares, with each ADS currently representing one Ordinary Share. This one‑for‑one ratio links trading in ADSs to the underlying Ordinary Shares.