[Form 4] Centessa Pharmaceuticals plc American Insider Trading Activity

Rhea-AI Filing Summary

Centessa Pharmaceuticals (NASDAQ: CNTA) Form 4 shows General Counsel Iqbal J. Hussain exercised 12,000 stock options at $5.84 and immediately sold the same number of ordinary shares at a weighted-average $14.02 on 06/24/2025 under a Rule 10b5-1 plan.

Post-transaction, Hussain’s direct ownership declined by ~10% to 105,386 shares; he also holds 5,500 shares indirectly and 291,559 unexercised options.

• Gross sale proceeds ≈ $168.2 K.
• Sale represents >5% of insider’s pre-sale direct holdings, meeting materiality threshold.
• No impact on share count or dilution.

Insider selling by a senior legal officer can be viewed as a potential sentiment headwind, though execution under a pre-arranged 10b5-1 plan mitigates timing concerns.

Positive

• None.

Negative

• General Counsel sold 12,000 shares (~10% of direct stake) for approximately $168K, a potential negative insider-sentiment signal

Insights

Insider Trading Analyst

GC exercises options, then sells 12k shares; 10% stake trim merits watch.

The $5.84 option exercise followed by a $14.02 sale locks in a 140% gain, netting roughly $168k. While the cash amount is modest, divesting over 5% of direct holdings triggers many insider-sell alert thresholds and may weigh on sentiment. The Rule 10b5-1 plan offers procedural cover, yet such plans often allow strategic flexibility. Hussain still retains 105,386 shares plus 291,559 unexercised options, indicating ongoing alignment. Market impact should be limited unless this sale precedes a pattern of continued disposals; investors should monitor future Form 4s for confirmation.

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^*

HUSSAIN IQBAL J

(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)
	General Counsel

3. Date of Earliest Transaction (Month/Day/Year)
06/24/2025

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)	06/24/2025		M		12,000	A	$5.84	117,386	D
Ordinary Shares(1)	06/24/2025		S(2)		12,000	D	$14.0182(3)	105,386	D
Ordinary Shares(1)								5,500	I	By spouse

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)	$5.84	06/24/2025		M			12,000	(4)	02/19/2031	Ordinary Shares(1)	12,000	$0	291,559	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 September 14, 2024.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.00 to $14.08, 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. 25% of the shares subject to such option shall vest and become exercisable on February 19, 2022 and the remaining 75% of the shares subject to such option shall vest and become exercisable in 36 monthly installments on the first day of each month thereafter.

Remarks:

	/s/ Gregory Weinhoff, attorney-in-fact	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 General Counsel Iqbal J. Hussain sell on June 24, 2025?

He sold 12,000 ordinary shares.

What was the weighted average sale price for the shares sold by CNTA's insider?

The weighted average price reported was $14.0182, with trades between $14.00 and $14.08.

What percentage of his direct holdings did Hussain dispose of in this transaction?

The sale represented roughly 10% of his direct stake prior to the disposition.

How many CNTA ordinary shares does Hussain own after the reported transactions?

He directly owns 105,386 shares and indirectly owns 5,500 through his spouse.

Were the sales executed under a Rule 10b5-1 trading plan?

Yes. The transactions were carried out under a Rule 10b5-1 plan adopted on September 14, 2024.

What were the exercise terms of the options used in the transaction?

Hussain exercised 12,000 options at $5.84 per share; the options expire on February 19, 2031.