POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that the undersigned hereby constitutes and
appoints each of Jeffrey P. Leduc and Christopher German the true and lawful
attorney-in-fact and agent, with full power of substitution and resubstitution,
for the undersigned and in the undersigned's name, place and stead, in any and
all capacities (until revoked in writing) to execute for and on behalf of the
undersigned, in any and all of the undersigned's capacities, any and all
statements on Forms 3, 4 and 5 with respect to the undersigned's holdings of and
transactions in securities issued by Repligen Corporation (the "Company") in
accordance with Sections 16(a) of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), and any and all regulations promulgated
thereunder, and to file the same, with all exhibits thereto, and any other
documents in connection therewith, with the Securities and Exchange Commission,
and with any other entity when and if such is mandated by the Exchange Act or by
the By-laws of the Financial Industry Regulatory Authority, granting unto said
attorney-in-fact and agent full power and authority to do and perform each and
every act and thing requisite and necessary fully to all intents and purposes as
the undersigned might or could do in person thereby ratifying and confirming all
that said attorney-in-fact and agent, or his substitute or substitutes, may
lawfully do or cause to be done by virtue hereof.

This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4 and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
foregoing attorney-in-fact.

IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of February 29, 2020.



                                      /s/ Rohin Mhatre
                                      --------------------------------------
                                      Name: Rohin Mhatre