Ironwood Pharmaceuticals Announces Partial Exercise of Underwriters' Option in Public Offering of Common Stock

Ironwood Pharmaceuticals

today announced that the underwriters of its previously announced public offering of shares of Class A common stock have partially exercised their option to purchase an additional 704,948 shares at a public offering price of $13.00 per share. These shares were purchased pursuant to the underwriters' option to purchase up to 1,575,000 additional shares in the offering. As a result, the Company has issued a total of 11.2 million shares in the offering and has received aggregate net proceeds, after underwriting discounts and commissions and other estimated offering expenses, of approximately $137.7 million. The initial offering of 10,500,000 shares closed on May 24, 2013. The closing for the additional 704,948 shares closed on June 4, 2013. J.P. Morgan and BofA Merrill Lynch served as joint bookrunning managers and as representatives of the underwriters for the offering. Morgan Stanley served as bookrunning manager for the offering. Cowen and Company, Ladenburg Thalmann & Co. Inc. and Mizuho Securities served as co-managers for the offering. A copy of the final prospectus supplement related to the offering has been filed with the Securities and Exchange Commission (SEC) and is available on the SEC's website located at www.sec.gov. Copies of the final prospectus supplement and the accompanying prospectus relating to this offering may be obtained from the offices of: J.P. Morgan, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, New York 11717 (telephone number: 866-803-9204) or from BofA Merrill Lynch, 222 Broadway, New York, New York 10038, Attention: Prospectus Department or by emailing dg.prospectus_requests@baml.com. The securities described above are being offered by Ironwood pursuant to an automatically effective shelf registration statement that was previously filed with the SEC. This press release shall not constitute an offer to sell, or the solicitation of an offer to buy, any of the securities, nor shall there be any sale of these securities, in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. About Ironwood Pharmaceuticals Ironwood Pharmaceuticals

is committed to the art and science of making medicines, from discovery through commercialization. We're focused on three goals: transforming knowledge into medicines that make a difference for patients, creating value that will inspire the continued support of our fellow shareholders, and building a team that passionately pursues excellence. Our first product, linaclotide, is approved in the United States and Europe. Our pipeline priorities include exploring further opportunities for linaclotide, leveraging our deep expertise in functional gastrointestinal disorders, and advancing programs in other areas such as allergic conditions, cardiovascular disease, central nervous system disorders and other conditions defined by patient symptoms. Ironwood was founded in 1998 and is headquartered in Cambridge, Mass.