Last year, for the first time, more patent applicants were filed in China than in the United States. This surge reflects China’s increasing intellectual property maturity and growing pains, according to U.S. intellectual property lawyers and experts.

In a Dec. 11 announcement, the World Intellectual Property Organization reported that in 2011 China’s patent office took in 526,412 applications, compared to 503,582 in the U.S. Patent and Trademark Office and 342,610 in Japan’s patent office.