Centessa (NASDAQ: CNTA) CEO has 604 shares withheld for RSU tax payment

Rhea-AI Filing Summary

Centessa Pharmaceuticals plc reported that Chief Executive Officer Mario Alberto Accardi had 604 Ordinary Shares withheld by the company to satisfy tax obligations arising from the vesting of restricted share units. This was a tax-withholding disposition, not an open-market trade. Following the withholding, he directly holds 243,282 Ordinary Shares, which may be represented by American Depositary Shares on a one-for-one basis.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Accardi Mario Alberto

Role Chief Executive Officer

Type	Security	Shares	Price	Value
Tax Withholding	Ordinary Shares	604	$39.42	$24K

Holdings After Transaction: Ordinary Shares — 243,282 shares (Direct, null)

Footnotes (1)

1. The Ordinary Shares may be represented by American Depositary Shares, each of which currently represents one Ordinary Share. Represents the number of shares withheld by the Issuer to cover tax withholding obligations in connection with the vesting of restricted share units.

Key Figures

Shares withheld for taxes: 604 shares Transaction price: $39.42 per share Shares held after transaction: 243,282 shares +1 more

4 metrics

Shares withheld for taxes 604 shares Tax-withholding disposition on Ordinary Shares

Transaction price $39.42 per share Value used for tax-withholding calculation

Shares held after transaction 243,282 shares Direct Ordinary Shares held by CEO post-transaction

Tax-withholding shares in summary 604 shares Reported as taxWithholdingShares in transaction summary

Key Terms

restricted share units, American Depositary Shares, tax-withholding disposition, transaction code F

4 terms

restricted share units financial

"tax withholding obligations in connection with the vesting of restricted share units"

Restricted share units (RSUs) are a promise from a company to give an employee or service provider actual shares or cash equal to the shares after certain conditions are met, typically staying with the company for a set time or hitting performance targets. Think of them like a time-locked gift card that becomes usable only after you’ve earned it. For investors, RSUs matter because they align employee incentives with company performance and can increase the number of shares outstanding over time, diluting existing ownership and affecting earnings per share.

American Depositary Shares financial

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

American depositary shares (ADSs) are a way for investors in the United States to buy shares of foreign companies without dealing with international markets directly. They represent ownership in a foreign company's stock and are traded on U.S. stock exchanges, making it easier for American investors to buy, sell, and own parts of companies from around the world.

tax-withholding disposition financial

"transaction_action": "tax-withholding disposition""

A tax-withholding disposition is an event or transaction—such as selling or transferring securities, exercising options, or receiving compensation—that triggers a requirement to hold back part of the payment and remit it to tax authorities. It matters to investors because it reduces the cash they receive immediately and can change the timing and amount of taxable income, like a cashier taking a portion of your sale proceeds to pay taxes before you get the rest.

transaction code F financial

"transaction_code": "F""

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^*

Accardi Mario Alberto

(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)

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/01/2026

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)	05/01/2026		F		604(2)	D	$39.42	243,282	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. The Ordinary Shares may be represented by American Depositary Shares, each of which currently represents one Ordinary Share.

2. Represents the number of shares withheld by the Issuer to cover tax withholding obligations in connection with the vesting of restricted share units.

Remarks:

	/s/ Raphael Deferiere, attorney-in-fact	05/18/2026
	** 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 transaction did Centessa Pharmaceuticals (CNTA) report for its CEO?

Centessa Pharmaceuticals reported that CEO Mario Alberto Accardi had 604 Ordinary Shares withheld to cover tax obligations from vesting restricted share units. This disposition was for tax payment purposes rather than an open-market stock trade.

Was the Centessa (CNTA) CEO transaction a stock sale on the open market?

No, the CEO’s transaction was not an open-market sale. The 604 Ordinary Shares were withheld by Centessa to cover tax liabilities tied to restricted share unit vesting, a compensation-related, non-market event disclosed in the Form 4 filing.

How many Centessa (CNTA) shares does the CEO hold after this Form 4 event?

After the tax-withholding disposition, CEO Mario Alberto Accardi directly holds 243,282 Ordinary Shares. These shares reflect his post-transaction ownership position as reported, separate from the 604 shares withheld for tax obligations on vested restricted share units.

What price per share is associated with the Centessa (CNTA) CEO tax-withholding?

The Form 4 lists a transaction price of $39.42 per Ordinary Share for the 604 shares withheld. This value is used to calculate the tax-withholding amount in connection with the vesting of restricted share units granted to the CEO as compensation.

How are Centessa (CNTA) Ordinary Shares represented in American Depositary Shares?

Centessa states that each American Depositary Share currently represents one Ordinary Share. This one-for-one relationship means the CEO’s reported 243,282 Ordinary Shares could correspond to the same number of ADS, depending on how they are held and traded.

What does transaction code F mean in the Centessa (CNTA) CEO Form 4?

Transaction code F indicates payment of an exercise price or tax liability by delivering securities. In this case, 604 Ordinary Shares were withheld by Centessa to satisfy tax withholding obligations when the CEO’s restricted share units vested, rather than sold on the market.