Established in April 2002, Changchun Law Firm is a comprehensive law firm with intellectual property as its core business. Headquartered in Beijing, it has branches in Shanghai, Guangzhou, and an office in the United States. There are currently 12 partners, including founding partners Si Yixia and Cang Yuchun; US-based partner Kenneth Ng; partners Xu Litian, Gao Yan, Liu Jianqiang, Li Gosheng, Meng Rui, Huang Yuan, Shen Huijuan, Xu Ruihong, and Hao Wenbo. Chang Tsi has 150 lawyers, trademark and patent agents. Changchun Law Firm was rated as an outstanding law firm in Beijing by the Beijing Lawyers Association in 2005. In 2012, it was rated as the best trademark agency in China in the first selection of China's Best Trademark Agency organized by the China Trademark Association. In recent years, Chang Tsi has been continuously selected as the best intellectual property firm in China by many internationally renowned legal rating agencies such as The Asia Pacific Legal 500, Chambers Asia Pacific, and Asia Law Profiles. The preferred law firm in the Chinese market for law firm, dispute resolution, intellectual property, and M&A business, "Top Ten Intellectual Property Law Firms in Greater China" and other dozens of awards, represented by founding partner Cang Yuchun. Most of them are outstanding lawyers and have won many individual awards for excellence.