Meizu is using technology that violates Qualcomm's patents without the usual licensing rigmarole, and Qualcomm isn't gonna take it anymore. So it is alleged in Qualcomm's press release, announcing a complaint against the up-and-coming Chinese manufacturer in the Beijing Intellectual Property Court. Qualcomm says that Meizu has refused to negotiate "in good faith" to license particular patents, especially those related to 3G and LTE radio standards, though the precise patents in question aren't delineated.

The press release makes Qualcomm's displeasure known in no uncertain terms:

Although Qualcomm would have preferred to reach a resolution with Meizu without the need for litigation, Meizu, unfortunately, has been unwilling to negotiate in good faith and enter into a license agreement on the rectification plan terms while unfairly expanding its business through the use of Qualcomm's innovations without compensating Qualcomm for the use of Qualcomm's valuable technologies.  In contrast, more than 100 other companies have already accepted the rectification plan terms, including the largest Chinese mobile device suppliers.

In addition to a thriving business-to-business portfolio of system-on-a-chip products, Qualcomm's extensive patent collection represents an important revenue stream for the company. Notably, this is a "complaint" to Chinese authorities, not a conventional lawsuit. Whether or not the American-owned Qualcomm can make headway in China's notoriously lax system of patent and copyright enforcement is questionable, but they seem to want to give it a go.