AGIOS PHARMACEUTICALS, INC. — Director's Dealing 2013

Jul 23, 2013

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: AGIOS PHARMACEUTICALS INC (AGIO)
CIK: 0001439222
Period of Report: 2013-07-23

Reporting Person: NELSEN ROBERT (Director, 10% Owner)

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Series A Convertible Preferred Stock	$		Common Stock (3636362)		Indirect
Series C-2 Convertible Preferred Stock	$		Common Stock (224374)		Indirect

Footnotes

F1: The Series A Convertible Preferred Stock is convertible into Common Stock on a 1-for-2.75 basis into the number of shares of Common Stock as shown in column 3 at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares have no expiration date.

F2: These shares are held 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"), which may be deemed to be the beneficial owner of the shares held by ARCH Fund VII. The sole general partner of ARCH Partners VII is ARCH Venture Partners VII, LLC ("ARCH VII LLC"), which may be deemed to be the beneficial owner of the shares held by ARCH Fund VII. Robert T. Nelsen, a member of the Issuer's board of directors, is a managing director of ARCH VII LLC and may be deemed to have shared voting and investment power over the shares held by ARCH Fund VII. Mr. Nelsen disclaims beneficial ownership of such shares, except to the extent of his pecuniary interest therein.

F3: The Series C-2 Convertible Preferred Stock is convertible into Common Stock on a 1-for-2.75 basis into the number of shares of Common Stock as shown in column 3 at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares have no expiration date.