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Bronze - Firms: prosecution

A compact team by market standards, An, Tian, Zhang & Partners operates as an elite squad of professionals, many of whom are both patent attorneys and qualified lawyers. The combination of prosecution and contentious experience helps clients on both ends – claims are drafted and won based on knowledge about what is most effective at the invalidation and infringement stages, while contentious proceedings can be handled by attorneys who know the prosecution history inside and out. David Tian is a seasoned litigator – big names such as Dell (China) and Daimler AG have trusted him to handle patent infringement disputes with local entities. One foreign associate on the litigation side remarks: “David and his colleague Ruifeng Li work seamlessly as part of my own team; our prompt and clear exchange of information and responsiveness makes them very easy to work with on patent instructions.”

Firm Profile

AN, TIAN, ZHANG & PARTNERS is a leading one-stop IP firm in China that serves mainly overseas clients. Its strong IP team works in a closely connected and task-oriented manner to manage large trademark, patent and copyright portfolios for clients in various fields. The team’s unique standard training system and supervision structure enable it to focus on detailed work. Moreover, the firm’s centralised training and quality supervision system has proven to be a strong help in the remote-working period of the Covid pandemic.

The IP team covers all aspects of the prosecution, litigation and enforcement of trademark, patent and copyright rights. The firm also deals with litigation relating to patent infringement, trademark registration and invalidation, copyright and other disputes arising in the IP field. Further, the firm’s close and smart structure enables it to assist clients with IP issues in an economical but exceptional way. In particular, the firm has sound experience enforcing patent rights relating to agriculture, automobile and lubricant products. The firm is also successful at conducting patent analysis to help clients to control the risks of their business investments. To understand clients’ needs, to solve their concerns and to become their reliable IP pillar in China is our constant goal.


Starting off 20 years ago as a trademark prosecution firm, AN, TIAN, ZHANG & PARTNERS has grown gradually and is now experienced in managing complicated portfolios and solving strategic disputes for international clients. With extensive knowledge of trademark regulation and practice, year after year the firm has helped clients obtain favourable outcomes in numerous opposition and invalidation cases through the administrative procedures and the subsequent litigations.

Building on its trademark prosecution and litigation successes, AN, TIAN, ZHANG & PARTNERS set up a patent team that is now also flourishing.


The patent team has grown rapidly in recent years and is experienced in handling patent litigation, prosecution and research in various fields. With its precise work and flexible response, the firm has attracted an increasing number of Japanese clients in need of patent prosecution and analysis in the machinery, pharmaceutical and automobile industries. The firm’s investigation team provides fantastic support for evidence collection, which is valuable in patent disputes and litigation. In addition, the firm set up a strong patent translation team to assist international clients. Patent analysis, such as freedom-to-operate reports, is part of the team’s daily work. The team handles more than 300 patent filings and invalidation cases annually.


Litigation is another key practice of the firm. The firm’s litigators are experienced in trademark, patent, copyright, unfair competition and administrative cases before the different courts across China. The firm’s close organisation enables its litigators to access the most up-to-date knowledge and provides an effective but economical litigation strategy for clients.

Enforcement and evidence collection

The firm has a trained team which deals with enforcement and evidence collection issues. It has experience operating across China and its members are knowledgeable in many industry areas. The team – under the supervision of litigators – conducts evidence collection, which is particularly important for patent infringement litigation. The team is also experienced in combating trademark and patent infringement in professional exhibitions, in the online and offline markets.

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