X0306 4 2018-08-24 0 0001446847 IRONWOOD PHARMACEUTICALS INC IRWD 0001478244 Currie Mark G C/O IRONWOOD PHARMACEUTICALS, INC. 301 BINNEY STREET CAMBRIDGE MA 02142 0 1 0 0 Chief Scientific Officer Class B Common Stock 2018-08-24 4 M 0 16667 4.89 A 791667 D Class B Common Stock 2018-08-24 4 M 0 41667 4.89 A 833334 D Class B Common Stock 2018-08-24 4 M 0 6666 5.48 A 840000 D Class B Common Stock 2018-08-24 4 S 0 65000 18.39 D 775000 D Class A Common Stock 30124 D Employee Stock Option (Right to Buy) 4.89 2018-08-24 4 M 0 16667 0.00 D 2019-02-11 Class B Common Stock 16667 0 D Employee Stock Option (Right to Buy) 4.89 2018-08-24 4 M 0 41667 0.00 D 2019-02-11 Class B Common Stock 41667 0 D Employee Stock Option (Right to Buy) 5.48 2018-08-24 4 M 0 6666 0.00 D 2019-07-28 Class B Common Stock 6666 20000 D This sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person. 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 $18.21 to $18.65, 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 was fully vested as of its grant date of February 12, 2009. The option vested as to 1.25% of the shares of Class B Common Stock on each monthly anniversary of January 1, 2009 for the first 36 months, and 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, 2013. The option vests in two equal installments based on the issuer's achievement of certain regulatory and commercial milestones. Upon achievement of a regulatory milestone, the option vested as to 20,000 shares of Class B Common Stock on January 4, 2017. /s/ Conor Kilroy, Attorney-in-Fact 2018-08-28