AGIOS PHARMACEUTICALS, INC. — Director's Dealing 2015

May 13, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AGIOS PHARMACEUTICALS INC (AGIO)
CIK: 0001439222
Period of Report: 2015-05-11

Reporting Person: NELSEN ROBERT (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2015-05-11	Common Stock	J	386074	—	Disposed	2702516	Indirect
2015-05-11	Common Stock	J	2229	—	Acquired	6689	Direct

Footnotes

F1: Distribution of Common Stock held by a limited partnership to its partners for no consideration.

F2: These shares are owned directly by ARCH Venture Fund VII, L.P. ("ARCH Fund VII"). The sole general partner of ARCH Fund VII is ARCH Venture Partners VII, L.P. ("ARCH Partners VII"). The sole general partner of ARCH Partners VII is ARCH Venture Partners VII, LLC ("ARCH VII LLC"). The Managing Directors of ARCH VII LLC, Robert T. Nelsen, Keith Crandell and Clinton Bybee, are deemed to have voting and dispositive power over the shares and may be deemed to beneficially own certain shares held by ARCH Fund VII. Each Reporting Person disclaims beneficial ownership of these securities, except to the extent of his pecuniary interest therein, and this report shall not be deemed an admission that such Reporting Persons are the beneficial owners of such securities for Section 16 or any other purpose.

F3: Change from indirect to direct ownership of shares previously reported as beneficially owned by the reporting person.