China

PATENT RE-EXAMINATION BOARD V. BEIJING WINSUNNY HARMONY SCIENCE & TECHNOLOGY CO., LTD. AND DAIICHI SANKYO CO., LTD. (2016) Administrative Retrial No. 41, SPC

Cause of action: Administrative dispute over invalidation of patent rights in an invention

Collegial panel members: Qin Yuanming | Li Rong | Ma Xiurong

Keywords: amendment, invalidation proceeding, inventive step (non-obviousness), Markush claim

Relevant legal provisions: Patent Law of the People’s Republic of China, article 31(1) Rules for the Implementation of the Patent Law of the People’s Republic of China, article 34

Basic facts: In the retrial of an administrative dispute over the invalidation of an invention patent under a “Markush claim” between the Patent Re-examination Board of the National Intellectual Property Administration, PRC (hereinafter the “Patent Re-examination Board”) and Beijing Winsunny Harmony Science & Technology Co., Ltd. (hereinafter “Winsunny”), with Daiichi Sankyo Company Ltd. (hereinafter “Daiichi Sankyo”) joined as a third party in the first-instance proceedings, Daiichi Sankyo was the holder of an invention patent No. 97126347.7 entitled “The preparation method of the pharmaceutical composition for the treatment or prevention of hypertension”. The patent claims were written in the form of a Markush claim. Winsunny asked the Patent Re-examination Board to invalidate the patent on the basis that it involved no inventive step.

On August 30, 2010, Daiichi Sankyo made the following amendments to the claim:

(a) it deleted “or ester” in the phrase “or its salt or ester which can be used for medicinal purposes” in Claim 1;

(b) it deleted “alkyl with 1 to 6 carbon atoms” under the definition of R4 in Claim 1; and(c) it deleted the other technical schemes except carboxyl and Formula COOR5a under the definition of R5 in Claim 1.

During the oral proceedings, the Patent Re-examination Board informed Daiichi Sankyo that the deletion of “or ester” in Claim 1 was approved, but that the other deletions were unacceptable since they did not conform to the relevant provisions under article 68 of the Rules for the Implementation of the Patent Law of the People’s Republic of China. Daiichi Sankyo and Winsunny did not object to this.

On January 14, 2011, Daiichi Sankyo submitted a revised claim for replacement in which “or ester” in Claim 1 was deleted. The Patent Reexamination Board issued Examination Decision No. 16266 on the Request for Invalidation (hereinafter “Decision No. 16266”), in which it decided that Claim 1 of the patent involved in the case was non-obvious as compared to that in Evidence #1, had an inventive step and conformed to article 22(3) of the Patent Law of the People’s Republic of China. Thus, on the basis of the revised version submitted by Daiichi Sankyo on January 14, 2011, the Patent Reexamination Board held that the patent right involved remained valid.

Opposing the decision, Winsunny initiated an administrative case before the Beijing No. 1 Intermediate People’s Court, which ruled that the Patent Reexamination Board had not erred in its application of law when it rejected Daiichi Sankyo’s revised text, as submitted on August 30, 2010, on the ground that it did not comply with article 68 of the Rules for the Implementation of the Patent Law. The court held that Claim 1 of the patent in question is non-obvious as compared to that in Evidence #1 and involves an inventive step; hence the Court decided to affirm Decision No. 16266.

Winsunny was not satisfied with the ruling and appealed. At second instance, the Beijing Higher People’s Court held that the Markush claim is a special type of parallel technical solution and that the revised text that Daiichi Sankyo submitted on August 30, 2010, narrowed the scope of protection for the patent involved, which complies with article 68(1) of the Rules for the Implementation of the Patent Law. The effect of a specific formulation covered by the claim of the patent involved is equivalent to the technical effect of Formulation #329 of the existing technology in Evidence #1. Claim 1 of the patent involved did not achieve the unexpected technical effect and therefore the second-instance courtheld that it did not involve the necessary inventive step.

Unhappy with this decision, the Patent Re-examination Board applied for permission to appeal to the Supreme People’s Court.

Held: On April 1, 2011, the Patent Reexamination Board issued Decision No. 16266, in which it affirmed that the patent right involved was valid.

Opposing the decision, Winsunny lodged an appeal with the Beijing No. 1 Intermediate People’s Court, which decided on December 20, 2011, to affirm Decision No. 16266. Winsunny refused to accept the first-instance judgment and appealed to the Beijing Higher People’s Court, asking the court to overturn both the judgment and Decision No. 16266, and to order the Patent Re-examination Board to make a new examination decision. On September 24, 2013, the second-instance court did indeed decide to overturn the decision at first instance and the Patent Re-examination Board’s Decision No. 16266, and to order the Patent Re-examination Board to review the case and arrive at a new examination decision.

Opposing this decision, the Patent Reexamination Board applied for permission to appeal to the Supreme People’s Court, which heard the case and delivered its judgment on December 20, 2017, reversing the second-instance decision and affirming that at first instance.

Reasoning: The Supreme People’s Court held as follows.

I. Nature of the Markush claim

A Markush claim is a special way of writing a claim in applications for chemical invention patents – that is, any patent application that covers the identification of multiple parallel optional elements in one claim. The way in which a Markush claim is written is designed to solve the problem in the field of chemistry wherein many substituent groups cannot be summarized by a common upper-level concept. It has been considered to be a structural expression rather than a functional expression. The Markush claim requires the definition of parallel optional elements instead of additional claims, where all of its optional compounds have common properties and functions and a common structure, or all of the optional elements belong to the same compound recognized in the domain of the invention. Although the Markush claim is written in a special way, it shall also comply with the requirements of unity expressed in provisions under the Patent Law of the People’s Republic of China and the Rules for the Implementation of the Patent Law of the People’s Republic of China. The strength of the Markush claim is its ability to generalize. Once the patent is granted, the scope of patent protection will cover all compounds with the same structure, property or function as that claimed, and the patentee’s rights and interests will be maximized. In essence, a patent right is the monopoly on a certain right, which means that the greater the scope of the rights enjoyed by the patentee, the more restrictions to which the public will be subject. For this reason, from the point of view of fairness, the Markush claim shall be interpreted strictly. No matter how many variables and combinations it includes, the Markush claim should be regarded as a general combination solution. The choice of a variable should generate a drug with the same effect, while the choice of different molecular formulas should produce different drugs, but there should not be too much difference in the drug’s efficacy and the drugs should be mutually replaceable, and the expected effect should remain the same. That is the reason why the Markush claim was created in the first place. Therefore, the Markush claim should be regarded as a collection of the Markush elements rather than of many compounds. Normally, the Markush elements should be understood as a class of compounds with common properties and functions, which would present themselves as a single compound only under certain circumstances. If it is determined that the compounds expressed under the Markush claim are a collection of many compounds, then the claim is inconsistent with the requirement of unity. It was consequently incorrect for the court of second instance to decide that the Markush claim is a parallel technical solution and its decision should therefore be corrected.

II. Amendment to a Markush claim in invalidation proceedings

The 2010 Guidelines for Patent Examination stipulate that, during the review stage of an invalidation request, any amendment to the new invention and utility patent documents shall be limited to the claims and shall adhere to the following basic principles.

(a) The title of the original claim shall not be changed.

(b) The scope of protection of the original patent shall not be extended as compared to the granted claim.

(c) The technical features shall not go beyond those of the original specification and claim.

(d) Generally, technical features that are not included in the granted claim shall not be added.

In the present case, however, the method of amendment employed, aside from meeting these principles, was specifically limited to the deletion of a claim, the deletion of a technical solution, the further limitation of a claim and the correction of an obvious error. “Further limitation of a claim” refers to the addition of one or more technical features recorded in other claims, so as to narrow the scope of protection.

It can be seen that, in invalidation proceedings, the amendment of patent documents can be effected in multiple ways. However, there are many special issues in the examination of patent application for chemical inventions, such as the fact that whether a chemical invention can be implemented needs to be confirmed by means of an experiment, that some chemical products need to be defined by means of parameters or preparation methods, and that the discovery of new properties of and uses for a chemical product do not mean changes in its structure or components. In view of the peculiarity of chemical inventions and given the fact that, in drafting a Markush claim, a patent applicant has had the opportunity to put as many structures and formulas as possible into one claim to obtain the maximum scope of protection, any amendment to a Markush claim at the invalidation stage should be strictly limited in scope. Amendment to the Markush claim shall be allowed only when the amendment will not generate a class of compounds, or a single compound, with new properties and functions; however, individual cases that merit exception should also be duly considered. If a patent applicant or a patentee is allowed simply to delete any option within any variable, then, even if such deletion will narrow the scope of protection and will not impair the rights and interests of the public, there will be such uncertainty in the possible new scope of rights protection that it will undermine the reasonable expectations of the public, as well as jeopardize the stability of the patent rights system. The decisions of the court of second instance in this regard are obviously improper and should be corrected.

III. Method for assessing the inventive step within a Markush claim

Assessment of the inventive step within a Markush claim should follow the basic “three-step method” stipulated in the Guidelines for Patent Examination. Unexpected technical effect is a contributing factor in judging the inventive step: it is a special kind of negative method of judgment and it does not have universal applicability. Thus only when an assessment of non-obviousness cannot be made based on the “three-step method” should a patent application be judged to involve an inventive step based only on unexpected technical effect. Generally, it would be inappropriate to skip the “three-step method” and directly apply the unexpected technical effect to determine whether or not a patent application involves an inventive step. As for the comparison of technical effects, in this case, the Patent Re-examination Board did not, in the invalidation proceedings, compare Formulations #10, #17, #50 and #69 of Document 1 with those of the patent and base its decision on that comparison; in the court of second instance, a direct comparison and decision was made, which obviously went beyond the scope of the requested review. Such a practice does not conform to the provisions of the Administrative Procedure Law of the People’s Republic of China and relevant judicial interpretations, and should be corrected.

Winsunny, which brought the invalidation proceedings, held that Claim 1 within the patent involved lacked the inventive step and used Evidence #1 as the closest comparative document. When deciding whether Claim 1 involves an inventive step or not, the Patent Re-examination Board and the court of first instance strictly followed the “three-step method”, finding that there are two distinguishing technical features between the compounds of Formula I in Claim 1 and the compounds of Formula I in Evidence #1. After analyzing the non-obviousness of the two distinguishing technical features, they believed that it was justified to declare that Claim 1 involves an inventive step. This Court affirms that finding.