Qualcomm is facing a trio of antitrust actions involving mobile phone chips in California courts, but antitrust may be the least of its worries right now. The U.S. Supreme Court’s May 30 decision on patent exhaustion seems to call into question Qualcomm’s entire business model.

Apple spotlighted the high court’s Lexmark decision in an amended complaint filed today in its San Diego antitrust case against the chipmaker. The Cupertino-based iPhone maker takes direct aim at Qualcomm’s practice of selling modem chips to Apple’s contract manufacturers while at the same time demanding royalties for Qualcomm’s contributions to the wireless technology.