REPLIGEN CORP — Director's Dealing 2012

Mar 19, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: REPLIGEN CORP (RGEN)
CIK: 0000730272
Period of Report: 2012-03-15

Reporting Person: HERLIHY WALTER C (Director, PRESIDENT, CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-03-15	Common Stock	M	50000	$3.24	Acquired	502203	Direct
2012-03-15	Common Stock	F	33265	$4.87	Disposed	468938	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-03-15	Stock Option (Right to Buy)	$3.24	M	50000	Disposed	2012-04-11	Common Stock (50000)	Direct

Footnotes

F1: Payment made via forfeiture of 33,265 shares of Common Stock valued at the Closing Price of $4.87 on March 15, 2012.