The family that owns the rights to Alvin and the Chipmunks has sued 20th Century Fox, claiming that it’s owed “half of all profits” from last year’s hit movie, Alvin and the Chipmunks: The Squeakquel, according to The Hollywood Reporter. In a lawsuit filed in U.S. District Court in Los Angeles, Bagdasarian Prods. and writer Janice Karman claim that the studio took substantial portions of a screenplay prepared for the sequel by Karman, the wife of the late creator’s son, without authorization. Separately, the suit alleges that Fox breached an agreement over promotional tie-ins using the Chipmunk characters. The 2009 movie made $442 million at the worldwide box office.

In a statement to the Reporter, Fox said, “the Bagdasarian’s claims are completely without merit. We look forward to resolving our differences and, in the meantime, we are continuing to move forward with the franchise.”