Introduction
This article aims to introduce the constraining impacts of donation rules and estoppel rules on the scope of protection of patent claims, and offer pertinent suggestions in the practical implementation of patent application/patent invalidation procedures.
Related legislation
Article 17 of the Decision of the "Several Provisions of the Supreme People's Court on Issues Concerning the Application of Law in the Trial of Patent Dispute Cases" revised in 2015 states: "The protection scope of an invention or utility model patent right referred to in Article 59, paragraph 1 of the Patent Law, which states that 'the protection scope of an invention or utility model patent right shall be determined by the content of the claim, and the description and drawings can be used to explain the content of the claim', refers to the protection scope of the patent right shall be determined by all the technical features recorded in the claims, and also includes the scope determined by equivalent features to the technical features. Equivalent feature refers to a feature that, by substantially the same means, achieves substantially the same function, achieves substantially the same effect, and can be conceived by a person skilled in the art without creative labor at the time when the alleged infringing act occurs."
Article 5 of the "Interpretation of the Supreme People's Court on Several Issues concerning the Application of Law in the Trial of Patent Infringement Dispute Cases" (hereinafter referred to as "Judicial Interpretation 1") passed in 2009 states: "For technical solutions described only in the specification or drawings but not recorded in the claims, if the patentee seeks to include them in the scope of patent protection in a patent infringement dispute, the people's court shall not support it."
Article 6 of the "Interpretation of the Supreme People's Court on Several Issues concerning the Application of Law in the Trial of Patent Infringement Dispute Cases" (hereinafter referred to as "Judicial Interpretation 1") passed in 2009 states: "In patent authorization or invalidation proceedings, if the patent applicant or patentee abandons a technical solution through modification of the claims or specification, or submission of opinions, the court will not support the inclusion of such solution in the scope of patent protection in a patent infringement dispute case."
The doctrine of equivalence is an important judicial principle developed in the practice of patent infringement trials in the United States. It is currently a legal principle in various countries' patent systems, with the aim of preventing accused infringers from easily avoiding liability and fairly protecting the legitimate rights of patentees. The purpose of the donation rules (Article 5 of the Judicial Interpretation
1) and the estoppel rules (Article 6 of the Judicial Interpretation 1) is to limit the improper application of the doctrine of equivalence, achieving a reasonable balance between the fair protection of the interests of patentees and the maintenance of the public interest.
For example, in the first case of drug patent linkage litigation in China (Civil Judgment No. 905 of the Supreme People's Court (2022)), the Supreme People's Court ruled that the technical solution adopted by the generic drug "Alendronate Sodium Capsules" did not constitute equivalence with the patented technical solution. Furthermore, in the judgment of this case, the Supreme People's Court also made it clear that the donation rules and the estoppel rules can both serve as limitations on the application of the doctrine of equivalence. The Supreme People's Court also clarified that the donation rules protects the reasonable expectations of the public based on the public notice effect of the patent document, and it is not related to whether the patentee subjectively intends to make a dedication.
This case has a guiding role in the promotion and implementation of the drug patent linkage system newly introduced in the amendment of the patent law in China. However, it also serves as a reminder for patentees to be aware that, in this case, the limitations of the donation rules and the estoppel rules led to the ultimate defeat of the patentee.
In the process of patent application and confirmation, patent applicants or patentees should pay close attention to the limitations of the donation rules and the estoppel rules on the protection scope of the claims, and avoid making statements or modifications that are unfavorable to themselves. In this regard, the author provides the following suggestions for practical application of patent application and confirmation:
1. The claims are consistent and clear with the description
The donation rule only compares the disclosed technical solutions in the specification with the claimed subject matter, and does not consider any statements made by the patentee during the examination process.
Technical solutions described only in the specification or drawings but not protected in the claims should be considered as "donated" to the public and cannot be asserted as infringement by applying the doctrine of equivalents in patent infringement litigation.
Therefore, patent applicants should ensure that the scope of protection in the claims is consistent with the corresponding disclosure in the specification or appropriately broader.
Additionally, patent applicants should provide clear definitions/explanations for the terminology used in the application, especially for unconventional interpretations, and have a correct understanding of the hierarchical relationships of different features. Ambiguous or unclear features should be avoided in the application. For example, for features with both broad and narrow interpretations, the applicant should provide a clear definition/explanation in the specification.
2. Pay attention to the layout of claims
Given the limitations on amending claims during the invalidation stage, it is advisable for patent applicants to strategically draft claims of varying protection levels in the patent application. The scope of protection for each level of claims should be comprehensive.
When drafting the application, the author suggests that the applicant conducts a thorough search for the technology to be protected and considers all alternative or obvious modifications when defining the scope of protection for each level of claims.
For claims that are difficult to limit through structural or component features, the author recommends considering the use of functional features for limitation. Functional features cover all ways of achieving the function. However, due to the increasingly strict judicial practice in China regarding the application of technical solutions using functional features, patent applicants should list as many possible implementation methods as possible when drafting the patent application. This will provide greater flexibility for the application of the doctrine of equivalents in subsequent infringement litigation.
3. Pay attention to how to modify claims
During the examination process, the patent applicant should carefully review the specification when amending the claims to avoid overlooking any possible alternative technical solutions mentioned in the specification. This is especially important when narrowing the claims to specific technical solutions. The applicant should also pay attention to whether there are similar alternative technical solutions in the entire specification.
It is important to note that, as clarified by the Supreme People's Court in the case mentioned above, the donation rules protects the reasonable expectations of the public based on the publication of the patent document, regardless of whether the patentee subjectively intends to dedicate the invention. Even if the patentee has no such intention, it does not affect the application of the donation rules.
Therefore, when responding to the examiner, the patent applicant should not only focus on the differences between the amended claims and the prior art, but also consider whether any other alternative technical solutions in the specification would be "dedicated" to the public.
For the defects pointed out by the examiner in the office action or rejection decision, if they can be overcome by means other than amendment, the patent applicant can communicate with the examiner and submit relevant arguments or evidence. For example, if a technical solution is not supported by the specification, the applicant can try to provide supplementary experimental data as proof. Although not all supplementary experimental data will be accepted, at least it will be considered by the examiner or the board.
4. Pay attention to the content of the opinion statement
Compared to the donation rules, the estoppel rules require a comparison of the changes in the protection scope of claims before and after the modification or the submission of the opinion statement.
It is important to note that explanations made by patent applicants during the examination process or by patentee during invalidation or litigation proceedings have a limited effect on the protection scope of claims.
Patent applicants or patentees should avoid overinterpreting the claims to address issues such as novelty/inventive step/support/adequacy of disclosure, which may result in the exclusion of certain technical solutions, especially unintentionally excluding certain technical solutions disclosed in the specification.
On the other hand, the public should also learn about the above rules. Understanding of claims should not be limited to the literal meaning of the claims, but should also consider the entire specification, application file amendments, and opinions submitted to determine the final protection scope of the claims, in order to advocate for their own interests beyond the protection scope of the patent.
The above is only a brief introduction by the author on the restrictive effects of the donation rules and the estoppel rules on the protection scope of patent claims. It is intended to provide some perspectives for patent applicants/patentees to consider in the practical operation of patent application/invalidation proceedings regarding the modification of patent application documents and the submission of opinions. If there are any inaccuracies in the text, please feel free to point them out and provide guidance.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
