The complaint said that Stern helped the company surpass its targets by more than 2 million subscribers in 2006 and 2007. After Sirius' merger with XM in 2008, Sirius XM again beat its targets, as well as in 2009 and 2010, according to the filing.
"Now that Sirius has conquered its chief competitor and acquired more than 20 million subscribers, it has reneged on its commitment to Stern, unilaterally deciding that it has paid him enough," the complaint said.
In response, Sirius XM said it had "met all of our obligations under the terms of our 2004 agreement with Howard, his agent and production company." It added it was "surprised and disappointed" by the legal action.