IRONWOOD PHARMACEUTICALS,INC. (NASDAQ:IRWD) Files An 8-K Material Modification to Rights of Security Holders
Item 3.03 Material Modification of Rights of Security Holders

On December31, 2018, all outstanding shares of ClassB Common Stock, par value $0.001 per share (the “ClassB Common Stock”), of Ironwood Pharmaceuticals,Inc. (the “Company”) automatically converted into the same number of shares of the Company’s ClassA Common Stock, par value $0.001 per share (the “ClassA Common Stock”), to the terms of the Company’s Eleventh Amended and Restated Certificate of Incorporation (the “Certificate of Incorporation”) (such automatic conversion being referred to as the “Conversion”). No additional shares of ClassB Common Stock will be issued following the Conversion.

The Conversion occurred to ArticleIV, SectionB(7)(c)of the Certificate of Incorporation, which provided that, among other triggers, each share of ClassB Common Stock would convert automatically, without any further action, into one share of ClassA Common Stock upon the later of (1)the first date on which the number of shares of ClassB Common Stock outstanding is less than 19,561,556, or (2)December31, 2018.

As required by Section243 of the Delaware General Corporation Law (“Section243”), the Company filed a certificate with the Secretary of State of the State of Delaware reciting that all shares of ClassB Common Stock had been retired and may not be reissued (the “Certificate of Retirement”). to Section243, the Certificate of Retirement also had the effect of eliminating from the Certificate of Incorporation all reference to ClassB Common Stock.

Prior to the Conversion, the shares of ClassA Common Stock and ClassB Common Stock generally had the same rights and privileges, ranked equally and shared ratably in dividends and distributions, except that each holder of shares of ClassA Common Stock was entitled to one vote per share on all matters subject to a stockholder vote and each holder of shares of ClassB Common Stock was entitled to ten votes per share on certain matters subject to a stockholder vote, including a merger involving the Company, a sale of substantially all of the Company’s assets and a dissolution or liquidation of the Company, and one vote per share on all other matters subject to a stockholder vote.

As a result of the Conversion, all holders of common stock now have one vote per share on all matters subject to a stockholder vote. The shares of ClassA Common Stock have the same voting powers, preferences, rights and qualifications, limitations and restrictions as the shares of ClassA Common Stock had prior to the Conversion, except to the extent that they have increased voting power in the certain limited matters described above due to the elimination of the ClassB Common Stock.

Following the Conversion, 100,000,000 shares of Common Stock that were previously designated as ClassB Common Stock are not designated to a series.

Upon Conversion, outstanding options denominated in ClassB Common Stock issued under any of the Company’s equity incentive plans remained unchanged, except that they now represent the right to receive shares of ClassA Common Stock rather than shares of ClassB Common Stock.

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