GT Advanced Technologies Inc., a parts supplier for Apple Inc., filed for bankruptcy, showing a partnership with the iPhone maker couldn’t assure success for its business of manufacturing lab-grown sapphire used to make mobile-device screens sturdier, Bloomberg News reported yesterday. Apple last November signed a deal to make a prepayment of about $578 million to GT Advanced to build furnaces used to make synthetic sapphire. When Apple introduced new iPhones last month though, the smartphones didn’t include the material. The lack of sapphire in the new iPhones was a surprise to those who had tracked the partnership, and the development exposed that GT Advanced had become overly dependent on Apple, said Pierre Maccagno, an analyst with Dougherty & Co. GT Advanced listed assets of $1.5 billion and liabilities of $1.3 billion as of June 28, according to its chapter 11 filing.
