Wang Yong 

Lawyer and patent attorney

 

On October 7, 2023, the Supreme People's Court of China (SPC) rendered the (2022) Zui Gao Fa Zhi Min Final No. 1584 Judgment, revising the judgment on invention patent infringement in Guangdong Galanz Microwave Oven Electrical Appliance Manufacturing Co., Ltd. (Galanz) v. Zhongshan Meige Electronic Technology Co., Ltd. (MeiG), and revoked the Guangzhou Intellectual Property Court (2020) Yue 73 Zhi Min Chu No. 2237 Civil Judgment. The SPC ruled that MeiG immediately stop manufacturing and using the riveting cap mold that infringed Galanz's invention patent (No. 201510373341.8) entitled riveting the lid mold for riveting the upper cover of the magnetron, and destroy the riveting mold, and pay Galanz RMB 10 million yuan in compensation of the damages, and RMB 200,000 yuan for its reasonable enforcement expenses.

 

After the judgment was rendered, the case attracted widespread attention and heated discussions, not only because the amount of damages was relatively large (RMB 10 million yuan), but also because the case was heard in open court hearing by the SPC Intellectual Property Tribunal on April 26, the World Intellectual Property Day 2023, with CGTN, CCTV, Kuaishou and other media platforms all broadcast it live, causing extensive social influence and effects.

 

In the SPC judgment, how the principle of infringement by equivalent was applied in this case was explained in more detail, and the non-infringement judgment made by the court of first instance was overturned. This author believes that this case represents, to a certain extent, the SPC latest views on the determination of infringement by equivalent, and has a strong exemplary effect. Following is an analysis of the trial process of the case based on the judgment, with an overview of the application of, and limitations on, the principle of equivalence in the judgment.

 

Basic facts and Trial Process

 

In magnetron products, whether the magnetron cover, as a key component to prevent microwave leakage, can be closely connected with the shell to form a closed cavity importantly impact the efficiency and safety performance of the magnetron. Galanz enjoys the invention patent No. 201510373341.8 (the patent at issue), which solves the problem of the upper cover of the magnetron which is difficult to rivet, with a simple structure and good riveting effect.

     

Galanz purchased a brand of microwave oven on multiple online shopping platforms, and the magnetrons used in it were all made by MeiG. Galanz alleged that MeiG had manufactured and used a large number of riveting cap molds that infringed its patent rights at issue to make magnetrons without permission, and sued in the Guangzhou Intellectual Property Court, requesting that MeiG be ordered to immediately stop manufacturing and using the allegedly infringing riveting cover molds, destroy the infringing products in use and inventory, and destroy the special equipment and molds for manufacturing the infringing products, and pay RMB 10 million yuan for the damages, and RMB 200,000 yuan for the reasonable enforcement expenses. After trial, the court of first instance concluded that the technical solution used in the allegedly infringing product did not fall within the protection scope of the patent at issue, and MeiG did not infringe Galanz’s patent involved in the case, and rejected all Galanz’s claims. Dissatisfied with the first-instance judgment, Galanz appealed the case to the SPC.

 

In the course of the first and second instance of the case, whether the riveting mold manufactured and used by MeiG was identical with, or equivalent to, the technical features stated in the claims of the patent at issue was the key to the dispute in this case. In order to avoid unnecessarily blurring the focus of this article, this author will not repeat the facts confirmed by both parties in the first and second instances, including the technical solutions.

 

In this case, the technical features in dispute in claims 1 and 2 which Galanz claimed were "the top of the wrestling arm (4) and the side force arm (5) are respectively connected to the power tooling through a transmission rod (3)" and "the upper power tooling (1) is connected to the wrestling arm (4) through a transmission rod (3), and the lower power tooling (2) is connected to the side force arm (5) through a transmission rod (3)" (hereinafter referred to as the transmission rod-related feature) in claim 1 at issue. In view of the above-mentioned disputed technical features, Galanz claimed that the allegedly infringing technical solution had technical features equivalent to the features relating to the transmission rod, which fell within the protection scope of the patent at issue. MeiG argued that the allegedly infringing product did not have a transmission rod, nor did it have the connection relationship and position relationship between each component and the transmission rod, and the various methods and effects of the two were different, so they were not the equivalent means of substitution.

 

The following is an analysis of the principles and provisions involved in the determination of patent infringement in this case, especially those related to infringement by equivalent, on the basis of the trial process of the first and second instances.

 

1. Principle of Comprehensive Coverage and Equivalence

 

The first paragraph of Article 59 of the Patent Law stipulates that "the scope of protection of a patent right for invention or utility model shall be subject to the content of its claims, and the description and drawings may be used to explain the content of the claims" (the Patent Law as amended in 2008 applied in this case). Article 2 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 stipulates that "the people's court shall, on the basis of the statements in, and the understanding of, the claims by a person skilled in the art after reading the description and drawings, determine the content of the claims provided for in the first paragraph of Article 59 of the Patent Law", and Article 7 stipulates that "the people's court shall determine whether the allegedly infringing technical solution falls within the scope of protection of the patent right, All the technical features stated in the claims asserted by the right holder shall be examined. If the allegedly infringing technical solution contains technical features that are identical with, or equivalent to, all the technical features in the claims, the people's court shall determine that it falls within the scope of protection of the patent; If the technical features of the allegedly infringing technical solution are less than one or more technical features stated in the claims compared with all the technical features in the claims, or if one or more technical features are not identical or equivalent, the people's court shall determine that it does not fall within the scope of protection of the patent."

 

The above-mentioned legal provisions and judicial interpretations are the legal basis for the principle of comprehensive coverage and the principle of equivalence in the determination of patent infringement.

 

The principle of comprehensive coverage and the principle of equivalence are the two most important principles for determining patent infringement. In judicial practice, when determining patent infringement, the principle of comprehensive coverage should first be used, that is, the technical features of the patent involved in the case and the allegedly infringing product are compared one by one, and when the two correspond each other and the corresponding technical features are exactly identical, it can be determined that the allegedly infringing technical solution falls within the protection scope of the patent. If a certain technical feature of the allegedly infringing technical solution is not identical with the corresponding technical feature of the patent, but the technical feature of the allegedly infringing technical solution adopts basically the same means, has basically the same function, and achieves the same effect compared with the patented technical feature, and a person skilled in the art can contemplate it without creative labor, the technical feature and the corresponding technical feature of the patent constitute equivalents. That is how the principle of equivalence works.

 

According to the interpretation of the SPC and the summary of judicial practice, it can be seen that basically the same means refer to the common means of substitution or replacement or means with basically the same working principle in the technical field to which the patent belongs at the time when the alleged infringement happens; basically the same function means that the role of the substitute means in the allegedly infringing technical solution is basically the same as that played by the corresponding technical features of the patent in the patented technical solution; and the basically same effect refers to the fact that there is no substantial difference between the technical effect achieved by the substitution means in the allegedly infringing technical solution and the technical effect of the corresponding technical features of the claims。

 

The legislative intent of the principle of infringement by equivalent is to limit the scope of patent protection based on the principle of fairness and reasonableness, so that the scope of patent protection is not only limited to the scope determined by the text of the claims, but also includes the scope determined by the features equivalent to the technical features in the patented claims.    

 

In this case, based on the principle of comprehensive coverage, the court of first instance compared the features of the allegedly infringing product with Galanz's claims one by one, and concluded that the transmission rod in claim 1 is an independent transmission structure used to connect the power arm tooling and the force arm, while the allegedly infringing technical solution does not have an independent transmission rod structure, and the power tooling is directly against the inner arc structure of the upper part of the power arm, so there is no connection relationship and position relationship related to the drive rod in claim 1, and it does not have the same technical features. Furthermore, the court of first instance, in light of the examination process of the patent, held that the structural features relating to the transmission rod are necessary technical features for claim 1 of the patent, and are the features of the invention point. It is further pointed out that, since the Patent Law protects inventive contributions, determination of infringement by equivalent should reflect the protection of the inventive contribution of the invention and ensure that the protection obtained by the patentee is commensurate with its technical contribution. It is precisely on the basis of the above reasons that the court of first instance held that the specific torque change solution for realizing the lever principle, i.e., the transmission rod and the related connection structure features, are necessary technical features for the claim 1 of the present patent, and are the features of the invention point, while the allegedly infringing technical solution adopts the torque change solution with an inner arc structure arranged on the upper part of the strength arm, and does not utilize the invention-point features of the patent at issue; therefore, the court of first instance did not determine the equivalence on the basis that the allegedly infringing technical solution finally delivered the result of riveting the upper cover, but emphasized the impact of the difference in technical means on the technical solution。

 

The SPC directly responded to the opinion of the court of first instance on the application of the principle of invention point and equivalence, corrected its determination on the invention point of the patent at issue, and discussed the relationship between the necessary technical features and the point of invention, that is, "the necessary technical features may include both features common to, and distinct from, the closest prior art, and they together constitute a solution for distinguishing from the prior art. The invention point that embodies the technical contribution usually refers to one or more features that solve the technical problem of the invention or utility model, and the necessary technical features are related to the invention point, but cannot necessarily be regarded as the features of the invention point". However, the SPC did not further discuss how the determination of the point of invention impacts the application of the principle of equivalence, and whether the so-called features of the invention point should be treated differently. In the judgment of this case, the SPC affirmed that "in the field of mechanical design, the cam structure and the connecting rod structure are commonly used transmission structure, the cam structure is the high-auxiliary transmission structure, and the connecting rod low-auxiliary transmission structure, and the replacement of the low-secondary product with the high-secondary or vise verse is a conventional and equivalent replacement method in the field of mechanical design", and concluded that "the allegedly infringing product and the patent at issue have had basically the same function performed with basically the same means, That is, the top of the wrestling arm and the edge arm can swing radially outward at the same time with the movement of the power tooling, so as to achieve basically the same effect, that is, the effect of riveting the four sides and four corners of the upper cover of the magnetron at the same time with a simple structure", thus determining that "the allegedly infringing technical solution has the technical features equivalent to the technical features at issue".

 

2. Invention Point and Equivalence Principle

 

Article 55 of the Guidelines for Determining Patent Infringement (2017) issued by the Beijing Higher People's Court provides that "if there are multiple equivalent features in the claims and the allegedly infringing technical solution, if the superposition of the multiple equivalent features causes the allegedly infringing technical solution to form a technical solution different from the technical concept of the claims, or if the allegedly infringing technical solution has achieved unexpected technical effects, it is generally not appropriate to determine that infringement by equivalent is constituted", and Article 60 provides that: "For the non-invention technical features in the invention claims, If the patentee knows or is sufficient to predict the existence of alternative technical features at the time of the patent application or amendment, but fails to include them in the scope of protection of the patent, the right holder's claim, made in the determination of infringement, that the alternative technical solution should be included in the scope of protection of the patent on the ground that it constitutes an equivalent feature shall not be supported." Obviously, the Beijing Municipal Higher People’s Court and some district courts held a view basically similar to that of the court of first instance in this case.

 

In contrast to the above-mentioned practice and guidelines, there are also cases where it is highlighted that no distinction should be made between invention and non-invention points. For example, in the case of Wenzhou Qianfeng Technology Co., Ltd. v. Wenzhou Ningtai Machinery Co., Ltd. ((2017) Zui Gao Fa Min Shen No. 2073), the SPC pointed out that "in the comparison of patent infringement, no distinction should be made between invention and non-invention points for the main reasons as follows: on the one hand,... When determining whether an invention or utility model patent is infringed, the principle of comprehensive coverage is applied, and no distinction is made between the invention and non-invention points. On the other hand, generally speaking, the former refers to the technical feature that reflects the contribution of the invention to the prior art among all the technical features of the claims of the patent at issue. It can be seen that the so-called invention and the non-invention points are relative to the closest prior art, and the difference of the closest prior art may lead to the difference of the point of invention. The relativity of the point of invention determines that it is not appropriate to distinguish between the invention and non-invention points in the comparison in cases of patent infringement."

 

Therefore, it can be seen that in judicial practice, there are great difference in considering the leniency of the equivalent scope of the technical feature from the perspective of whether the corresponding technical feature is the point of invention.    

 

In this case, although the SPC corrected the determination of the point of invention by the court of first instance, it failed to consider the leniency of the scope of equivalence of technical features or how it affects the application of the principle of equivalence based on the re-identified point of invention. Therefore, it can be held that the SPC does not believe that a larger or smaller scope of equivalent protection should be granted to the features of the point of the invention at present, considering the amount of creative labor put in by the inventor.
 

For this author, whether one or more technical features are points of invention involves the evaluation of patentability, which is usually used in the examination stage of a patent application in the evaluation of inventive step, which is itself a topic that is not easy to determine. Moreover, for the technical solution defined in the claims, the invention points are often different relative to different references. It is likely to be problematical in practice to consider the width of the equivalence of technical features from the perspective of whether the corresponding technical features are invention points. Therefore, the relativity of the invention point determines that it is not appropriate to distinguish between the invention and the non-invention points in the comparison for determining patent infringement.

 

3. Principle of Estoppel and Infringement by Equivalent       

 

In the determination of patent infringement, it is generally believed that the claims define the boundaries of the scope of protection of a patent, and the public (especially the competitors of the patentee) evaluate whether their actions would constitute patent infringement based on what are stated in the claims. Since infringement by equivalent expands the scope of protection of the patent beyond the literal meaning of the claims, the public would find it less certain in assessing whether their actions would constitute patent infringement based on the statements of the claims, and the public notifying function of the claims will be affected to a certain extent, so it is necessary to impose certain restrictions on the principle of equivalence. The function of the principle of estoppel is to limit the application of infringement by equivalent to an appropriate scope, for the purpose of ensuring the public notifying function of the claims, and avoiding harm done to the public interests.

 

It is stipulated in 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 that if a patent applicant or patentee abandons a technical solution by way of amendment made to the claims or description or statement of opinion during the patent grant or invalidation procedure, and the right holder includes it in the scope of patent protection in a patent infringement dispute case, the people's court shall not support the inclusion.  

 

Pursuant to the judicial interpretation, the court no longer supports the technical solution that has been abandoned by way of amending the claims. A restrictive or defining amendment to the claims is possibly a restrictive amendment to the existing technical features in the original claims, narrowing down the scope of the existing technical features in the original claims, thereby narrowing down the scope of protection of the technical solution defined in the claims; A restrictive amendment to the claims is also possibly to add a new technical feature to the original claims, thereby narrowing down the scope of protection of the technical solution defined in the claims. The principle of estoppel applies to both amendments. However, it is not clear in practice to what extent infringement by equivalent could still apply to the amended technical features.

 

In this case, in the first CNIPA office action with regard to the patent at issue, the examiner held that "claim 1 of the application text lacks the necessary technical features to solve the technical problem", and considered that the structural features relating to the transmission rod are necessary technical features to solve the technical problem of the present invention. The patent applicant's submissions show that the patent was granted as claims 2, 3, 4 and 5 of the original text of the patent application at issue were merged into claim 1. That is, in the applicant's original text, claim 1 does not have a feature of the specific structure of the transmission rod, but only a feature description of the lever principle, that is, "by using the lever principle, the bottom of each force arm acts inward at the same time to rivet the side riveting cover die and the corner riveting cover die to rivet the skirt of the upper cover". When the examiner considers that it lacks the necessary technical features, the applicant adds the features relating to the transmission rod (i.e., the original claims 2, 3, 4 and 5) to the original claim 1 to address the defect of lacking the necessary technical features. However, this amendment limits the feature of the lever principle originally summarized to specific transmission rods and related structural features, and whether this amendment excludes other solutions that conform to the lever principle other than the relevant features of the transmission rod, that is, The SPC's judgment did not discuss whether "driving the wrestling arm and the edge arm to swing outward at the same time through the upward movement of the cam on the inner arc surface of the wrestling arm and the edge arm in the allegedly infringing product is the technical solution that was abandoned due to the amendment made to the description or in the statement of opinions in the patent grant or invalidation procedure" and the one that was "included in the scope of patent protection in patent infringement dispute case".

 

Article 13 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(II) promulgated in March 2016 restricts the scope of application of the principle of estoppel and adds the element of "express denial" as an exception to the application of the principle of estoppel, namely, where the right holder proves that the patent applicant or patentee expressly denies the restrictive amendment to, or statement on, the claims, description and drawings in the patent grant and confirmation procedure, the people's court shall determine that the amendment or statement has not led to the abandonment of the technical solution.

 

In the case (2017) Zui Gao Fa Min Shen No. 1826, the SPC further clarified the "express denial" provided in Article 13 of the Judicial Interpretation (II), that is, an objective and comprehensive judgment should be made on the examination of the technical features in the patent grant and confirmation stage, focusing on whether the restrictive statement made by the right holder on the technical solution was finally recognized by the adjudicator, and whether the patent application was granted or the patent right was maintained. However, judging from the entire process of the trial, the amendment to the patent involved in the case during the examination process was recognized by the CNIPA, resulting in the grant of the patent to the application at issue, and this is not a case of "express denial" as mentioned in the preceding judicial interpretation.

 

4. Predictability Rule and Infringement by Equivalent

 

It is generally believed that there are two clear restrictions on the application of infringement by equivalent in the determination of patent infringement, namely, the principle of donation and the principle of estoppel. However, in the judicial practice, there is an unwritten principle for restricting infringement by equivalent, that is, the principle of predictability. To date, the Patent Law and judicial interpretations have not yet clearly defined the meaning of the principle of predictability, but it has been at play in judicial decisions.

 

According to the currently generally accepted interpretation, the principle of predictability of the principle of equivalence means that the principle of equivalence cannot include technical solutions that the patentee could have predicted at the time of applying for a patent and should be covered within the scope of protection of the claims.

 

Although China's Patent Law and relevant judicial interpretations do not explicitly provide for the predictability rule, it is clearly supported in the Guidelines of the Beijing Higher People's Court for Determining Patent Infringement (2017). Article 60 of the Guidelines stipulates that: "For non-invention point technical features, technical features formed in the amendment, or technical features in the claims of a utility model, if the patentee clearly knows or it is sufficient for him or it to predict the existence of alternative technical features in the patent application or amendment at the time of the patent application or amendment, but fails to include the technical features in the patent, and the right holder claims inclusion of the alternative technical solution in the scope of protection of the patent in the infringement determination on the ground that it constitutes an equivalent feature, the claim shall not be supported."

 

At the same time, in the judicial practice in China, the predictability rule has been applied to considerable, specific cases, especially in the recent SPC judgments. For example, in Beijing Xingao Technology Co., Ltd. v. Taiyuan Caiwei Manor Characteristic Agricultural Development Co., Ltd., a case of infringement of utility model patent (SPC Judgement (2019) Gao Gao Fa Min Shen No. 3188), the SPC held that "in terms of the technical features of the elastic support sheet and other heights, it is sufficient for the applicant of the patent involved in the case to predict the existence of this alternative feature at the time of the patent application, but did not include it in the claims of the patent at issue. Therefore, the technical features of the contour arrangement of the elastic support pieces should not be recognized as the technical features equivalent to the ‘alternating arrangement of the high and low elastic support pieces' in claim 1 of the patent at issue." In the judgement (2021) Zui Gao Fa Zhi Min Zhong No. 192, the SPC held that if the patentee had clearly known the relevant technical solution when drafting the patent application, but had not included it in the scope of protection of the claims, the equivalence principle should no longer be applied to include the technical solution in the scope of protection in the infringement lawsuit. To determine whether the patentee is clearly aware of, and protects, a specific technical solution at the time of patent application, it can be determined based on the contents of the description and drawings, and the description and drawings should be treated as a whole, and the standard for judgment lies in the understanding of those skilled in the art after reading the claims, description and drawings.

 

During the second-instance trial of this case, to further prove that in the field of mechanical design, the cam mechanism and the connecting rod mechanism are both commonly used transmission mechanisms in the field, Galanz provided multiple evidence, including textbooks related to mechanical principles, and in the pre-trial inquiry of the second instance, two university professors were also invited to participate in the inquiry as expert assistants, and expressed their opinions on whether the connecting rod structure and cam structure in the mechanical field are common mechanical design methods that could be replaced with each other. In the judgment of the second instance, the collegial panel concluded that "in the field of mechanical design, the cam structure and the connecting rod structure are commonly used transmission structures, with the former being a high-auxiliary transmission structure, and the latter a low-auxiliary transmission structure. Replacement of the low auxiliary with the high auxiliary or vise verse is a conventional and equivalent replacement method in the field of mechanical design," and "For those with ordinary skill in the art of machinery, it is easy to contemplate replacing the low-side structure of the conventional connecting rod structure with a conventional cam and a high-auxiliary transmission structure with a rolling contact with an inner camber", and it was thus determined that "the allegedly infringing technical solution has technical features equivalent to the technical features at issue".

 

Judging from the facts disclosed in the above-mentioned trial, it is clear that the SPC held that before the filing date, in the field of mechanical design, the cam structure and the connecting rod structure are commonly used transmission structures, and it was easy to contemplate replacing the conventional low-auxiliary structure of the connecting rod structure with a conventional high-auxiliary transmission structure with a conventional cam, and vise verse. If, according to the rule of predictability, the allegedly infringing product in this case adopts a torque change solution in which an inner arc structure is set at the upper part of the arm, that is, the power tooling moves back and forth on the inner arc structure of the upper part of the arm, and the torque is different in thickness of the middle part, and then the wrestling arm and the side arm are driven to swing to realize the clamping or loosening of the upper cover, it should be the content that can reasonably be predicted and written into the claims during the drafting or examination of the application documents. However, there is no record of this relevant feature in Galanz's patented claims. It is worth noting that in this case, the SPC did not comment on the facts and the principle of predictability.

 

Undoubtedly, the principle of predictability places extremely high demands on claims drafting. If the patentee wants to avoid the principle of predictability from becoming an obstacle to the accusation of infringement by equivalent, it should try to summarize the technical features at a higher level when drafting the claims, and summarize all the technical means known on the filing date in the technical features. Of course, this is the proper essence of claims drafting. In the case (2015) Min Shen Zi No. 740, the SPC believed that "with the further popularization and development of the patent system, the patentees will be more capable of drafting patent documents, and the patent administration department has become more stringent with the drafted patent applications, and the protection, based on the equivalence principle, for patents with a lower level of drafting has been gradually less effective". It can be seen that the principle of predictability has the effect of promoting the improvement of the drafting skills from the beginning.

 

However, on the other hand, requiring a patentee to summarize all the technical means that he should have known before the filing date is possibly too idealistic, and will result in a much higher drafting cost, or even makes it a mission impossible. If the principle of predictability is not strictly constrained and restricted, it will inevitably form a trend of overhead equivalence. Although the principle of predictability was not embodied in this case, a series of rulings the SPC has rendered in recent years have demonstrated the potential power of the principle, which has forced patentees, patent attorneys and lawyers to pay more attention to it, strive to improve the application drafting skills and be more cautious when amending the claims, so as to deliver the SPC's hope of reducing the protective effect of the principle of equivalence on low-level patents.

 

Conclusion

 

Since the principle of equivalence was first established in China in 2001, the SPC, with more than 20 years of judicial practice, has gradually refined the conditions for, scope and methods of application of the principle of equivalence in terms of the "three basic identicalness + obviousness" through judicial interpretations and rich judicial precedents, and has also imposed necessary restrictions on the application of the principle of equivalence through explicit and non-explicit principles, such as the principle of redundant designation, principle of infringement by inferior modification, principle of comprehensive coverage, principle of donation, principle of estoppel, principle of deliberate exclusion, and rule of predictability. While providing effective legal protection for patentees and encouraging technological innovation, it is also ensured that the scope of protection of patent rights has sufficient legal certainty and predictability to protect the legitimate rights and interests of the public. Therefore, imposing necessary restrictions on the principle of equivalence to prevent excessive application of infringement by equivalent is also the direction that has been highlighted and explored in the judicial practice in China. As stated in the judgment of the first instance: "Determination of infringement by equivalent should not only be based on the comparison of the means, functions and effects of the technical features; it is not possible to simply consider the equivalent on the basis of 'differences' of technical means, and it is often subjective to judge whether it is a ‘substantially the same means' and the features that can be easily contemplated without creative work in the field of technology." However, this author believes that only by continuous judicial practice, earnest experience summarization and theoretical discussions, gradually exploring and summarizing some effective principles and rules, improving the judicial capability, minimizing the subjectivity of adjudication, and increasing objectivity and predictability, can we provide adequate and appropriate protection for patentees, and deliver the purpose of promoting scientific and technological progress and social fairness.