Markush claims in China - what can be arbitrarily deleted during invalidation?
Since 2010, the China Patent Re-examination Board (PRB) has published the top 10 patent invalidation cases of the year in April of each year. The selection criteria are high social concern, significant impact on the related industry, or involve difficult legal issues and important examination criteria. Below is one of the top 10 cases that discusses post filing data in China patents.
This case (Beijing Winsunny Harmony Science & Technology Co., Ltd. v. Daiichi Sankyo Co., Ltd) describes an invalidation request of Daiichi Sankyo’s Chinese invention patent 97126347.7 related to processes of preparing pharmaceutical compositions for treating or preventing hypertension. The patent covered the marketed hypertension drug Olmesartan medoxomil.
During the invalidation, the patentee made select amendments to multiple Markush groups, deleting particular individual components from several different R groups of a molecule. The issue at hand is whether these amendments are allowable during an invalidation proceeding, which typically has very strict rules regarding amendments.
Courts Differ on Markush Claims in China
In short, it boils down to how the courts interpret a Markush claim. Does it refers to a general technical solution or parallel embodiments of several technical solutions? If it is one general solution, should you really be able to pick and carve away at its scope? Does doing so create a new scope that has a different technical effect than the original invention? If so, is that allowable?
The Patent Re-examination Board (PRB) and the Beijing High People’s Court (BHPC) disagreed on how to interpret Markush claims in China. The PRB felt that arbitrary amendments should not be allowed because a Markush claim is directed towards a general technical solution. Arbitrarily deleting elements during invalidation would thus create new scopes of protection that could have different technical solutions.
The BHPC thought that Markush groups represented alternate parallel technical solutions, and thus deleting one or more options just narrowed the scope of the claim. The Supreme People’s Court (SPC) ruled that the amendments were allowable. Additionally, the SPC indicated that such types of amendments may be allowed during invalidation as long as the amendments did not generate a scope that possessed a new function or technical effect.
Markush Claims in China Drafting Tips
Applicants should be aware that amendments which carve out a new scope with improved technical effect (as compared to the original scope) may not be allowable. During an invalidation proceeding, it will be difficult to amend claims to a narrower scope with improved technical results to overcome inventive step. Instead, at the time of drafting, applicants should draft several dependent claims directed towards alternate scopes with varying qualities of efficacy, including very narrow claims covering the best, most efficacious compounds. It is risky to rely on being able to carve out scope from broader claims during an invalidation challenge.
A side note on inventive step . . .
Interestingly, this case also briefly discussed inventive step. The petitioners argued that the patent lacked inventive step because a specific embodiment in the patent had equivalent technical effect as a prior art compound. The PRB disagreed and emphasized that inventiveness is actually a three-step determination, and it is inappropriate to directly apply just the “unexpected technical effect” test to see if claims are inventive or not.
Sources: Lexology, Sanyou IP Group
New Policies to Promote Importation of Innovative Drugs
2018年11月8日
At the April 12, 2018 executive meeting of the State Council in China, Premier Mr. Li Keqiang indicated the government’s desire to increase China’s access to innovative drugs. To achieve this, the government would encourage importation of innovative drugs into China by streamlining the regulatory pathway, enhancing IP protection, and lowering the cost of medicine. […]
阅读更多 >
What Kind of Damage Awards Can You Get in China?
2022年6月16日
Is it worth filing for a patent in China? What kind of damage awards can you get? Pharma companies care more about injunction than damage awards, since it’s quite unlikely that any damage award can compensate for the large amounts of money that may be lost for patent infringement. Chinese courts often issue injunctions in […]
阅读更多 >
AI is magical but NOT magic! Be specific in your AI patents!
2025年1月9日
What is the standard of sufficient disclosure for AI-related patents: A case study in China The rapid growth of AI patent applications present significant challenges to existing patent application and examination practices. One of them is satisfying the requirement for sufficient disclosure. The following case was featured in the 2023 CNIPA Compilation of Key Decisions […]
阅读更多 >
RNAi Patent Success in China: Overcoming “Comprising” Claim Challenges
2025年3月10日
An Update on Sufficiency and Inventiveness of RNAi Patents in China RNAi is a fast-developing technology that has gained traction in the pharmaceutical industry as a promising therapeutic agent. It is important to follow closely RNAi patent proceedings to learn how different examination boards and courts understand and handle these new technologies. The first-ever invalidation […]
阅读更多 >
我们的过去活动
Insights from HKSTP Market Discovery - BIO Connect
2025年5月28日
HKMHDIA Medical Fair Forum
2025年5月27日
Celebrating Innovation at the Asia Summit for Global Health
2025年5月26日
Eagle IP Celebrates 20th Anniversary, Reflecting on Two Decades of Excellence
2025年5月21日
Eagle IP is Coming Back to LSPN in Boston!
2025年4月24日
AIPLA Women in IP Global Networking Event in Hong Kong
