Qualcomm’s China Tech Day conference in January in Beijing represented a who’s who of China’s mobile industry. Top executives from the country’s biggest handset makers showed up. But one Chinese smartphone giant, Huawei, was notably absent.

Huawei, the world’s third-largest smartphone maker behind Apple and Samsung, used to be a major Qualcomm customer. But over the past seven years, it has gradually turned into a competitor by developing its own mobile chips and accumulating more intellectual property related to new wireless technology. That shift now poses a threat to both Qualcomm’s chip sales and, increasingly, to its lucrative patent royalties.