(Reuters) - A judge has dismissed radio shock jock Howard Stern's lawsuit accusing Sirius XM Radio Inc of failing to pay him stock awards he claimed were due for helping the satellite radio company exceed growth targets.

New York State Supreme Court Justice Barbara Kapnick in Manhattan said "the clear, unambiguous language" of the 2004 agreement that brought Stern to what became Sirius XM prevented him from prevailing.

Had all the performance-based provisions been triggered, Sirius could have owed Stern's production company, One Twelve Inc, an additional $300 million and his agent, Don Buchwald, an additional $30 million, according to Monday's decision.

Sirius shares were up 0.9 percent at $2.19 in trading before the market opened.

The case is One Twelve Inc et al v. Sirius XM Radio Inc, New York State Supreme Court, New York County, No. 650762/2011.

(Reporting by Karen Freifeld and Jonathan Stempel in New York; Editing by Lisa Von Ahn)