After filing for bankruptcy, GT Advanced says SEC is conducting an inquiry into its business

Sapphire materials maker GT Advanced Technologies, which filed for Chapter 11 bankruptcy reorganization in October, said Thursday that the Securities and Exchange Commission has opened an inquiry into its business.

The company said the SEC is looking into trading in its securities, its sapphire business, and securities offerings going back to Jan. 1, 2013. The agency is asking the Merrimack, New Hampshire, company for documents. GT said it is cooperating with the SEC.

The company filed for bankruptcy reorganization on Oct. 6. It says the SEC sent a letter on Oct. 15 saying it was conducting the inquiry.

GT Advanced Technologies Inc. announced in 2013 that it would supply scratch-resistant sapphire materials to Apple Inc. for use in cameras and other devices. However, it struggled to get a manufacturing facility up and running, and when the iPhone 6 went on sale in September, it had a standard glass screen. On Oct. 23, the company said it would leave the glass-making business and focus on making equipment used in processing sapphire materials.

It will try to sell almost 2,000 furnaces it had installed in an Arizona factory to make materials for Apple and will use the proceeds to repay the $439 million it had received from Apple as an advance payment. The plan requires approval from a bankruptcy court judge.