Hong Kong CNN  — 

Chinese technology company Huawei filed two lawsuits against Verizon in US courts on Thursday.

The Chinese company is suing the US carrier seeking compensation for alleged unauthorized use of Huawei patents for optical transmission, digital communications and related services.

Huawei is the world’s largest telecommunications equipment maker and a leading smartphone brand. But the Shenzhen-based company has a very limited presence in the United States, where it has been barred from supplying core equipment to major US carriers for years.

Nevertheless, Huawei’s technology has found its way into the US network because Verizon buys telecommunications equipment that uses the Chinese company’s technology from other vendors. Some of that equipment, according to Huawei, doesn’t have cross-license agreements.

“For years now we have successfully negotiated patent license agreements with many companies,” Huawei chief legal officer Song Liuping said in a press release.

“This is the common practice in the industry. Huawei is simply asking that Verizon respect Huawei’s investment in research and development by either paying for the use of our patents, or refraining from using them in its products and services,” he added.

The lawsuits did not indicate how much Huawei is seeking in compensation from Verizon. A spokesperson from Verizon did not immediately respond to a request for comment.

The latest legal action is part of Huawei’s broader strategy of fighting Washington’s pressure campaign on the Chinese company through US courts and public opinion.

Last March, Huawei sued the US government over a law that banned federal agencies from buying its products. In December, it sued the US government again, this time over new restrictions from the Federal Communications Commission.

Huawei executives have published op-eds in the Wall Street Journal and USA Today, insisting that it is a private company and “not a tool of the Chinese government.”

The company has also dramatically upped its spending on Washington lobbyists to nearly $3 million last year, compared to $165,000 in 2018, according to Open Secrets, a nonprofit, nonpartisan research group based in Washington.

Washington maintains that Huawei poses a national security threat and has taken several steps to curb its business, including barring US companies from supplying the Chinese firm with key tech and software. The Trump administration has also argued that installing Huawei’s equipment in US networks could allow Chinese spies to eavesdrop on sensitive US communications. Huawei denies the allegations and says none of its products poses a national security risk.

Despite the prolonged American campaign against its business, Huawei managed to increase sales to 850 billion yuan ($122 billion) in 2019, up 18% from the previous year.