Matthew Gault, reporting for Motherboard: The Federal Trade Commission put six companies on notice in early April for illegally telling customers that getting third-party repairs voids the warranty on their electronics. You've seen the stickers before and read the messages buried in end user license agreements. Plastered on the back of my PlayStation 4 is a little sticker that says "warranty void if removed." That's illegal. Motherboard has obtained copies of the letters via a Freedom of Information Act request and has learned the names of the six companies that were warned. They are Sony, Microsoft, Nintendo, Hyundai, HTC, and computer hardware manufacturer ASUS. The letters were sent by Lois Greisman, the FTC's associate director of marketing practices, on April 9; the FTC has given each company 30 days to change its official warranty policies and says that it may take legal action against the companies.