REPLIGEN CORP — Director's Dealing 2015

May 12, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: REPLIGEN CORP (RGEN)
CIK: 0000730272
Period of Report: 2015-05-08

Reporting Person: RYAN THOMAS F JR (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2015-05-08	Common Stock	S	20000	$37.19	Disposed	20312	Direct

Footnotes

F1: $37.19 is a weighted average price. These shares were sold in multiple transactions at prices rangining from $37.00 to $37.83, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.