Larimar Therapeutics, Inc. — Director's Dealing 2015

May 18, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ZAFGEN, INC. (ZFGN)
CIK: 0001374690
Period of Report: 2015-05-15

Reporting Person: STARR KEVIN P (Director, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2015-05-15	Common Stock	J	1000000	—	Disposed	3202045	Indirect
2015-05-15	Common Stock	J	443935	—	Acquired	443935	Indirect
2015-05-15	Common Stock	J	443935	—	Disposed	0	Indirect
2015-05-15	Common Stock	J	92041	—	Acquired	172138	Direct

Footnotes

F1: Distribution of shares in kind by Third Rock Ventures, L.P. ("TRV") on a pro rata basis to its partners.

F2: The shares are directly held by TRV. The general partner of TRV is Third Rock Ventures GP, L.P. ("TRV GP"). The general partner of TRV GP is TRV GP, LLC ("TRV GP LLC") and the Reporting Person is a Manager of TRV GP LLC, as such, each of TRV GP and TRV GP LLC and the Reporting Person exercises shared voting and investment power over the shares held of record by TRV. The Reporting Person disclaims beneficial ownership of the shares except to the extent of his pecuniary interest therein, if any.

F3: TRV GP received shares distributed in kind by TRV on a pro rata basis to its partners.

F4: The shares are directly held by TRV GP. As such, each of TRV GP LLC and the Reporting Person exercises shared voting and investment power over the shares held of record by TRV GP. The Reporting Person disclaims beneficial ownership of the shares except to the extent of his pecuniary interest therein, if any.

F5: Distribution of shares in kind by TRV GP on a pro rata basis to its partners.

F6: The Reporting Person received shares distributed in kind by TRV GP on a pro rata basis to its partners.