REPLIGEN CORP — Director's Dealing 2014

Mar 3, 2014

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: REPLIGEN CORP (RGEN)
CIK: 0000730272
Period of Report: 2014-02-27

Reporting Person: WITT DANIEL P (Senior Vice President)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2014-02-27	Common Stock	A	6182	—	Acquired	53891	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2014-02-27	Stock Option (Right to Buy)	$15.91	A	11842	Acquired	2024-02-27	Common Stock (11842)	Direct

Footnotes

F1: Mr. Witt was awarded 6,182 Restricted Stock Units. Each Restricted Stock Unit represents a contingent right to receive one share of Repligen Corporation's Common Stock. 2,060 Restricted Stock Units vest on 2/27/2015. 2,061 Restricted Stock Units vest on each of 2/27/2016 and 2/27/2017. The Restricted Stock Units may be settled only by delivering shares of Repligen Corporation's Common Stock, and thus, the grant is being reported in Table 1 as allowed per SEC guidance.

F2: 3,947 shares vest and become exercisable on each of 2/27/2015 and 2/27/2016. 3,948 shares vest and become exercisable on 2/27/2017.