Tessera Technologies Inc. has declared patent war on its largest customer.

Tessera and its subsidiaries brought 10 actions against Samsung Electronics Co. across the United States and Europe on Thursday, alleging that the company's smartphones infringe 24 patents covering semiconductor processing, bonding and packaging.

San Jose, California-based Tessera makes its money licensing semiconductor design technology to some of the world's largest electronics companies. Tessera parent Xperi Corp. reported earlier this year that Samsung accounted for 25 percent of its revenues, or about $65 million, making the Korean smartphone maker its largest customer. Tessera and Samsung have been licensing partners for 20 years, a relationship that was just expanded in 2014, but ended last December.