August 2, 2013 (Shareholders Foundation) - An investor, who currently holds shares of Optimer Pharmaceuticals, Inc. (NASDAQ:OPTR), filed a lawsuit in effort to halt the proposed takeover of Optimer Pharmaceuticals, Inc. by Cubist Pharmaceuticals, Inc.
The plaintiff alleges that the defendants breached their fiduciary duties by agreeing to sell the company at an unfair price via an unfair process.

On July 30, 2013, Cubist Pharmaceuticals, Inc. and Optimer Pharmaceuticals, Inc. announced that they have signed a merger agreement under which Cubist Pharmaceuticals, Inc will acquire all of the outstanding shares of Optimer Pharmaceuticals, Inc common stock for $10.75 per share in cash, or approximately $535 million on a fully diluted basis. In addition to the upfront cash payment, each stockholder of Optimer Pharmaceuticals, Inc will receive a Contingent Value Right (CVR), which is expected to be publicly traded, entitling the holder to receive an additional one-time cash payment of up to $5.00 for each share they own if certain net sales of DIFICID®(fidaxomicin) are achieved, or a total transaction value of up to $801 million on a fully diluted basis.
However, the plaintiff claims that the offer is too low and undervalues the company. Indeed, NASDAQ:OPTR shares traded as high as $16.35 per share on May 16, 2013 and at least one analyst set a price target of $25.00 per NASDAQ:OPTR share.

Shares of Optimer Pharmaceuticals, Inc. closed on August 2, 2013, at $12.51 per share.