X0306 4 2017-10-13 0 0001374690 ZAFGEN, INC. ZFGN 0001441724 Heller Frances K C/O ZAFGEN, INC. 175 PORTLAND STREET, 4TH FLOOR BOSTON MA 02114 1 0 0 0 Common Stock 2017-10-13 4 P 0 10000 3.8988 A 47961 D The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.8645 to $3.92, inclusive. The reporting person undertakes to provide to Zafgen, Inc., any security holder of Zafgen, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth herein. Total number of shares includes 7,961 shares of Common Stock acquired by the Reporting Person on December 31, 2012 that were not previously reported. /s/ Laurie Burlingame, Attorney-in-Fact 2017-10-17