Repligen (RGEN) SVP uses company shares to cover RSU taxes

Rhea-AI Filing Summary

Repligen Corp senior vice president of R&D Ralf Kuriyel reported two tax-related share dispositions. On February 27, 2026, the company withheld 444 shares of common stock at $128.73 to cover tax obligations from restricted stock units vesting.

On March 2, 2026, the company similarly withheld 923 shares at $124.97. After the later transaction, Kuriyel directly owned 14,695 common shares. These were tax-withholding events rather than open-market sales.

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

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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^*

KURIYEL RALF

(Last) (First) (Middle)

C/O REPLIGEN CORPORATION

41 SEYON ST., BLDG 1, STE 100

(Street)

WALTHAM MA 02453

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
REPLIGEN CORP [ RGEN ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Senior VP, R&D

3. Date of Earliest Transaction (Month/Day/Year)
02/27/2026

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	02/27/2026		F		444(1)	D	$128.73	15,618	D
Common Stock	03/02/2026		F		923(1)	D	$124.97	14,695	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 the number of shares withheld by the Issuer to satisfy tax withholding obligations of the reporting person that arose upon the release of restricted stock units.

	/s/ Jennifer Carmichael (Attorney in Fact)	03/03/2026
	** 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).
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FAQ

What insider transactions did Ralf Kuriyel report at Repligen (RGEN)?

Ralf Kuriyel reported two tax-related share dispositions. On February 27, 2026, 444 shares were withheld, and on March 2, 2026, 923 shares were withheld, both to satisfy tax obligations from restricted stock units vesting.

Were Ralf Kuriyel’s Repligen (RGEN) Form 4 transactions open-market sales?

No, the transactions were not open-market sales. The reported dispositions were shares withheld by Repligen to satisfy tax withholding obligations that arose when restricted stock units for Ralf Kuriyel were released, according to the filing’s explanatory footnote.

How many Repligen (RGEN) shares does Ralf Kuriyel hold after the reported transactions?

After the March 2, 2026 tax-withholding disposition, Ralf Kuriyel directly owned 14,695 shares of Repligen common stock. This figure reflects his direct ownership following the issuer’s withholding of shares to cover his tax obligations on vested restricted stock units.

What was the price per share in Ralf Kuriyel’s Repligen tax-withholding events?

The issuer withheld shares at specific prices tied to each event. On February 27, 2026, 444 shares were valued at $128.73 each, and on March 2, 2026, 923 shares were valued at $124.97 each, according to the Form 4 disclosure.

Why did Repligen withhold shares from Ralf Kuriyel’s equity awards?

Repligen withheld shares to meet tax withholding obligations when Ralf Kuriyel’s restricted stock units were released. Instead of paying cash, a portion of the vested shares was withheld by the issuer, as described in the Form 4 footnote, to cover the associated tax liability.