X0508 4 2024-02-29 0000730272 REPLIGEN CORP RGEN 0001733143 KURIYEL RALF C/O REPLIGEN CORPORATION 41 SEYON ST., BLDG 1, STE 100 WALTHAM MA 02453 false true false false Senior VP, R&D false Common Stock 2024-02-29 4 A false 404 0.00 A 27480 D Common Stock 2024-03-01 4 F false 453 191.79 D 27027 D Represents 404 shares issued pursuant to a Performance Stock Unit ("PSU") award granted to the Issuer on February 24, 2021. The Compensation Committee authorized the issuance of the underlying shares based upon the Issuer's achievement of pre-established performance criteria set forth in the PSU award. 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/ Kimberly Brown (Attorney in Fact) 2024-03-04