Patent service is one of core services in Chang Tsi & Partners. As the “Top-Tier Intellectual Property Firm in Asia Pacific” and “Best Intellectual Property Firm in China” appraised by a host of authoritative legal rating agencies such as Chambers Asia Pacific and China Law & Practice, Chang Tsi & Partners provides patent legal services in the core service fields and wins a wide recognition in industry. Chang Tsi & Partners has been consecutively appraised as Leading Patent Law Firm by Managing IP (Patent) since 2014, has been listed as “Highly Recommended Patent Law Firm in China” for 4 consecutive years by IAM Patent 1000 in the list of top worldwide patent agencies, and is also appraised as “Outstanding Patent and Trademark Law Firm in China” by Managing IP.


Globally-oriented Chang Tsi & Partners approaches intellectual property from a resolutely commercial perspective and utilizes sophisticated client and file management systems to ensure a seamless customer experience. Domestic and international patrons receive a dedicated service from three specialist teams – electrical, mechanical and biochemistry – and are never left in the dark as to the progress of prosecution or litigation efforts. The squad practices in English, Chinese and Japanese – a further draw for global players.


Chang Tsi & Partners boasts exceptionally excellent Chinese patent professionals, and most of them have science or engineering and law academic background. Over one third of practitioners have the qualifications of practicing lawyers and patent attorneys in China, and one fourth of practitioners have received education in other countries and are holders of patent agency qualifications in the United States and other countries. The patent attorneys in Chang Tsi & Partners not only have expertise in patent laws of China, the United States, Japan, and European countries, but also are proficient in languages such as English, Japanese and German. Our patent team consists of litigation lawyers who have many years’ litigation experience and former senior judges and patent examiners who have the experience in court IP trial and worked in the Patent Reexamination Board under the SIPO, as well as experts who are both lawyers and scholars. With a goal of maximizing the clients’ interests in light of clients’ needs, we are capable of proposing strategic, professional and innovative solutions to complicated legal issues and providing comprehensive, multilayered and one-stop legal services to clients.


Our competitive strengths:

Philosophy and practicing objective of maximizing clients’ interests


Team of professional interdisciplinary talents

Institution --- a law firm with patent agency qualifications and specialized in providing IP services.

Team --- a team consisting of five partners and over 50 interdisciplinary talents, wherein most of them have more than ten years’ patent practicing experience; many have the lawyer qualifications and patent attorney qualifications, have a grasp of professional skills and the law, and are proficient in foreign languages.

Experience and skills --- we have dealt with a host of complex disputes and litigation cases, and thus accumulated rich experience and possess more professional legal skills compared with other agencies; we have the capability of more acute risk judgment and recognition, and thus are capable of avoiding potential legal risks when providing patent legal services.

Management---excellent and professional attorney team, strong workflow management team, strict quality control system, efficient time limit supervision.

Operation ---corporate management and team operation can integrate all resources in the law firm and provide comprehensive services to clients.


Comprehensive, multilayered and one-stop



As for the business scope, the patent services in Chang Tsi & Partners cover every aspect of patent matters, including invention, utility model, design, proprietary technology, trade secrets, product packaging and decoration, protection of new plant varieties, layout design of integrated circuits, patent management and assignment and unfair competition associated with patent, consumer rights and interests, product liability, advertisement and other fields.


Including levels such as acquisition and maintenance of rights, protection of rights, commercial operation of rights and enterprise IP strategy.

Acquisition and maintenance of rights: patent layout, preparation of patent application documents, patent application, handling of notification of office action, invalidation for reexamination, administrative litigation of patent right verification, management of annual fees and patent maintenance.

Protection of patent rights: market investigation and monitoring, infringement analysis and proposals for protection against infringement, non-litigation dispute settlement (lawyer’s letter and claim for non-litigation infringement), administrative complaints on patent infringement, and civil action and criminal litigation against patent infringement.

Commercialization of patent rights: assessment of patent value, due diligence of patent lawyers, patent licensing and assignment, special legal services in the process of commercialization of patents and the like.

Enterprise patent protection strategy: including patent analysis of competitors, proposals for patent global layout of enterprises, proposals for patent management architecture of enterprises, and patent management process of enterprises and specification formulation.


We have rich experience in patent invalidation, patent administrative complaint and patent civil litigation. Meanwhile, our vision of business is not limited to patents, since we have rich experience of combining patents with other intellectual property rights, such as trademarks, copyrights, special package and decoration of well-known goods, and anti-unfair competition. A favorable judgment is not the end of our service, and we have a wealth of experience and success stories in promoting enforcement of such judements.


International Perspective

International working standards, international management and operation, and promote a long-term, extensive and closely-bonded business cooperation worldwide. Furthermore, the control systems of workflow and quality on the same level as globally-acclaimed practices.


Corporate Management and Team Operation

With regard to important or complicated cases, we have the ability to mobilize all the resources in the firm to deal with them; and we have a perfect team spirit and philosophy in a team consisting of attorneys, patent agents and investigators.


Customization and Result Orientation

In the process of acting on a case, we will, based on the case conditions and litigation objective of the client, aim at achieving the benefit maximization of the client, and creatively providing a customized solution for the client, so as to seek the accomplishment of the litigation objective. The win rate of the cases of patent invalidation that we represent can be more than 80%, including the cases both of declaration of invalidation on behalf of a petitioner, and of declaration of invalidation on behalf of a patent holder.

The number of litigations on patent we represent has amounted to more than 200, with a win rate of 90% whether on behalf of a plaintiff or a defendant.


Services We Can Offer:

  • Assisting clients in setting up comprehensive strategies for patent protection, participating in setting up management system for patents and technological innovations, drafting standard of operation for patents and technological innovations
  • Providing scientific, technological and patent intelligence information, including competitors’ patent portfolio investigation and competitors’ patent landscape analysis.
  • helping enterprises organize and formulate standards for worldwide patent portfolio’s verification and maintenance, including patent planning and landscaping, patent application and annuity payment services worldwide
  • Schematic designing and negotiation for patent licensing, transfer and other patent commercialization
  • Drafting, reviewing, and amending legal documents for patent assignment and licensing
  • Patent searches, patent and legal status monitoring
  • Drafting and filing patent applications for inventions, utility models, and designs
  • Filing and defending for patent re-examination and invalidation
  • Filing administrative litigation for patent related matters
  • Providing Customs recordal and Customs training services
  • Investigations and evidence collection for patent infringement
  • Participating in administrative actions and arbitration for patent disputes
  • Filing and defending administrative actions for patent infringement
  • Filing and defending patent infringement litigations, including civil and criminal cases
  • Patent annual fee payment and docketing services
  • Due diligence for patents
  • Providing patent valuation services
  • Providing legal services for patent related antitrust and misuse
  • Rendering patent related opinions, including Freedom-to-operate opinions, non-infringement opinion