A California man, Timothy Smith, has filed a lawsuit against Apple in a Santa Clara County Superior court, accusing the company of turning his unlocked iPhone into useless piece of electronics. In court papers filed by Smith’s attorney Damian Fernandez, it is alleged that Apple is violating California’s antitrust laws.

Smith argues in court papers filed Friday and made available at InfoWeek Apple is in violation of California’s Cartwright Act because “Apple prohibits iPhone consumers from using and purchasing a cell phone service other than through AT&T.” The case may also hinge on a clause in the Digital Millennium Copyright Act that Fernandez interprets to mean a carrier-subsidized phone can be unlocked 90 days after purchase.