With a representative office in Tokyo, Beijing Sanyou Intellectual Property Agency is known for having a large Japanese client base that includes Panasonic, Olympus, Honda and Seiko Epson. The firm recently added telecommunications provider Huawei, China's largest PCT company filer, to its local client portfolio, which also includes China National Petroleum Corporation and Tongrentang, a famous Chinese medicine company. Beijing Sanyou puts a lot of emphasis on the quality of work and it has a specialised quality control department that consists of experienced agents and former patent examiners to ensure the quality of its output.