Centessa insider nets $139k in 10b5-1 sale, keeps 122k shares

Rhea-AI Filing Summary

Centessa (NASDAQ:CNTA) Form 4 reports that Chief Business Officer Gregory M. Weinhoff exercised 10,000 options at $3.85 and immediately sold the same 10,000 ordinary shares on 06/25/2025 through a Rule 10b5-1 plan.

The shares were disposed at a weighted-average price of $13.8642, yielding roughly $139 k in gross proceeds and an implied ~$10 per-share spread. After the transactions he still owns 122,279 ordinary shares (≈8 % reduction versus post-exercise balance) and 65,000 unexercised options. The sale exceeds the 5 % materiality threshold for insider trades, making the activity noteworthy for investors tracking executive sentiment.

Positive

• None.

Negative

• Chief Business Officer sold 10,000 shares (≈8 % of his direct stake) for about $139 k, which can be perceived as a bearish insider signal.

Insights

Insider Trading Analyst

8 % stake reduction via option cash-out; slightly negative insider signal.

The transaction combines a low-priced option exercise ($3.85) with an immediate market sale at $13.86, locking in a ~260 % gain. Although the dollar amount (~$139 k) is modest, parting with 10,000 shares trims Weinhoff’s direct ownership by about 8 %, signaling mild profit-taking. The use of a 10b5-1 plan cushions interpretation—orders were pre-scheduled, reducing informational asymmetry concerns—but investors often view any executive sale above 5 % as a bearish data-point. Importantly, the officer maintains a sizeable 122 k-share position plus 65 k options, suggesting continued long-term alignment. Still, the selling pressure could weigh on sentiment in the near term, particularly if followed by additional insider disposals.

Portfolio Strategist

Rule-based sale appears routine; limited balance-sheet impact for Centessa.

Because the transaction is option-funded, no cash leaves Centessa’s coffers and share count is unchanged—the shares sold were newly issued upon exercise. Liquidity impact is thus neutral for the company. From a portfolio standpoint, the 8 % reduction is small relative to Weinhoff’s remaining stake, which keeps insider ownership above 120 k shares. The sale may reflect personal diversification rather than deteriorating outlook, especially as it was pre-planned. Unless additional insiders replicate the pattern or volumes escalate, the event is unlikely to alter fundamental valuation models. Watch for follow-up filings to confirm whether this is an isolated monetization or the start of a broader insider selling trend.

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^*

Weinhoff Gregory M

(Last) (First) (Middle)

C/O CENTESSA PHARMACEUTICALS PLC

3RD FL., 1 ASHLEY RD, ALTRINCHAM

(Street)

CHESHIRE X0 WA14 2DT

(City) (State) (Zip)

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 Business Officer

3. Date of Earliest Transaction (Month/Day/Year)
06/25/2025

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
Ordinary Shares(1)	06/25/2025		M		10,000	A	$3.85	132,279	D
Ordinary Shares(1)	06/25/2025		S(2)		10,000	D	$13.8642(3)	122,279	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)	$3.85	06/25/2025		M			10,000	(4)	02/01/2033	Ordinary Shares(1)	10,000	$0	65,000	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 May 22, 2024.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.60 to $14.06, 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, 2023.

Remarks:

	/s/ Gregory M. Weinhoff	06/25/2025
	** 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

How many CNTA shares did the Chief Business Officer sell on 25 June 2025?

Gregory Weinhoff sold 10,000 ordinary shares at a weighted-average price of $13.8642.

What percentage of Gregory Weinhoff's CNTA holdings was sold according to the Form 4?

The sale represented approximately 8 % of his directly held shares.

How many CNTA shares does Gregory Weinhoff still own after the transaction?

He retains 122,279 ordinary shares and holds 65,000 unexercised options.

At what price were the options exercised versus the sale price?

Options were exercised at $3.85 and the shares were sold at a weighted-average of $13.8642, a ~$10 spread.

Was the transaction executed under a Rule 10b5-1 trading plan?

Yes. The Form 4 states the sales were carried out under a 10b5-1 plan adopted on 22 May 2024.