X0306 4 2014-12-16 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 2014-12-16 4 M 0 15987 2.94 A 315987 D Class B Common Stock 2014-12-16 4 S 0 15987 14.01 D 300000 D Employee Stock Option (Right to Buy) 2.94 2014-12-16 4 M 0 15987 0.00 D 2017-01-22 Class B Common Stock 15987 34013 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 $13.99 to $14.09, inclusive. The reporting person udertakes 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 as to 1.25% of the shares of Class B Common Stock on each monthly anniversary of January 1, 2007 for the first 36 months, and vested as to 4.5833% of the shares of Class B Common Stock on each monthly anniversary thereafter. The option was fully vested as of January 1, 2011. /s/ Halley E. Gilbert Attorney-in-Fact 2014-12-18