X0306 4 2013-03-05 0 0001446847 IRONWOOD PHARMACEUTICALS INC IRWD 0001478521 Higgins Michael J C/O IRONWOOD PHARMACEUTICALS, INC. 301 BINNEY STREET CAMBRIDGE MA 02142 0 1 0 0 Chief Operating Officer Class B Common Stock 2013-03-05 4 S 0 50000 15.57 D 141666 D Class B Common Stock 2013-03-06 4 M 0 100000 0.60 A 241666 D Employee Stock Option (Right to Buy) 0.60 2013-03-06 4 M 0 100000 0.00 D 2013-07-15 Class B Common Stock 100000 33334 D In order to effect the sale, these shares of Class B Common Stock were converted into shares of Class A Common Stock in accordance with the issuer's certificate of incorporation. The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $15.50 to $15.79, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. The option vested in installments upon the issuer's achievement of certain market capitalization, financing and clinical milestones. The milestones were met, and the option was fully vested as of December 31, 2006. /s/ Halley E. Gilbert Attorney-in-Fact 2013-03-07