Qualcomm today said it has filed 17 fresh complaints in China against Meizu Technology Co, stepping up its battle with the Chinese smartphone maker after the two were unable to reach a licensing agreement. Last Friday, Qualcomm filed one more patent infringement complaint against Meizu - one of China's top 10 handset suppliers - to intellectual property courts in Beijing and Shanghai.

Qualcomm is seeking to uphold terms of its landmark 2015 anti-trust settlement with China's economic policy panel, the National Development & Reform Commission (NDRC). The U.S. company agreed to pay a fine of $975 million in the settlement, the largest in China's corporate history.

"Meizu has refused to engage in good-faith negotiations despite admitting that it sells products that infringe Qualcomm’s valuable Chinese patents," said Don Rosenberg, executive vice president and general counsel, Qualcomm Incorporated. "Meizu is attempting to obtain an unfair and improper cost advantage over its competitors. Regrettably, we must turn to court actions in order to protect our rights, and importantly, to maintain fairness and a level playing field for the more than 100 Chinese companies that are respectful of patent rights and have entered into license agreements in conformance with the resolution reached by Qualcomm with the NDRC."

The 17 latest patent infringement complaints cover a range of features and technologies used in smartphones, Qualcomm said, including those relating to 3G (WCDMA and CDMA2000) and 4G (LTE) wireless communications standards.

China accounted for 53 percent of Qualcomm's global revenue of $25.28 billion for the fiscal year ended Sept. 27, with a large chunk of profit coming from higher-margin royalties earned from the company's licensing arm.