Apple took a hit in China after the country’s intellectual property bureau ordered Apple Inc to stop the sales of its iPhone 6 and iPhone 6 Plus citing that it broke patents of a local firm. Shenzhen Baili, a little-known startup, won a surprise injunction against sales of Apple’s iPhone 6 and iPhone 6 Plus in Beijing, based on a patent covering smartphone design. Apple said the order had been stayed pending appeal and sales remain unaffected.

The patent ruling is the latest challenge for Apple in China, its largest market outside of the U.S. After years of rapid growth, iPhone sales fell in China in the quarter ended March 26, contributing to Apple’s first quarterly revenue decline in 13 years. Chinese companies are learning to take advantage of a maturing domestic patent system, laying claim to patents even if they weren’t the first to develop the broader technology, said Erick Robinson, chief patent counsel for Asia Pacific at the Rouse China law firm.