WASHINGTON, Jan. 15 (Xinhua) -- The total number of U.S. grant patents for Chinese mainland companies increased in 2018 as all other countries declined, an indication of strengthened innovative ability and effort on the part of Chinese companies to expand long-term presence in the U.S. market, an expert has told Xinhua.

The U.S. utility grants declined in 2018, affecting all regions of the world except Chinese mainland, according to the annual report released recently by IFI Claims, a New Haven-based patent service.

Larry Cady, IFI Claims senior analyst, told Xinhua in an exclusive interview that Chinese companies are doing a lot of research and development and they are filing patents on those inventions in both China and the United States.

Cady said such growth against trend was because those companies consider the United States a large market for their products, especially high-tech ones in computers and telecommunication.

Their incentives to apply patents in the United States are "defensive" moves to avoid being sued for copying, according to Cady. It comes as some Chinese companies going into patent troubles in the United States since they're not that familiar with the American patent system.

Rankings for U.S. patent assignees showed that China's Huawei Technologies ranked 16th place, registering 1,680 patents, which is a 14 percent growth year on year. Huawei is followed by BOE Technology Group, a Chinese display manufacturer, registering 1,634 patents.

Cady said that the patent applications were long-term business strategies, so they're not affected by the short-term trade tensions between China and the United States.

China made great advances in its innovation and the trend is expected to continue, said Cady.