中國Court CasesInvalidationPharma
2018年12月4日

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
Other Top 10 Cases summarized in this blog
Can Post Filing Data Overcome Inventive Step in China? How to craft allowable claim scope around sequences to comply with China’s strict written description requirements
Jennifer Che, J.D. is a US Patent Attorney and Vice President and Partner at Eagle IP, a Boutique Patent Firm with offices in Hong Kong, Shenzhen, and Macau. [email protected]

其他文章

China Releases Draft Examination Guidelines for the new Patent Law

2020年12月4日
The Chinese Patent Office (CNIPA) is moving forward at breakneck speeds aiming to get all the necessary pieces in place for the June 1, 2021 date when the new 4th Amendment of the Patent Law will come into effect. Most recently, this means a flurry of drafts coming out from CNIPA, including, but not limited […]

China’s Newest Examination Guidelines: Novelty and Inventive Step for Compounds (Part II)

2021年4月29日
This is Part II of a three-part series summarizing the Examination Guidelines that were released by the CNIPA on January 15, 2021, one year to the date of Phase 1 of the US and China Economic and Trade Agreement. That agreement included specific provisions where China "shall permit pharmaceutical patent applicants to rely on supplemental […]

What is the difference between an Invention Patent and a Utility Model Patent?

2021年8月13日
There are two types of patent protection in China. Invention patents (similar to a US utility patent) have a term of 20 years from the date of filing and may be granted for both methods and products. Utility model patents (similar to a petty patent) may be granted in China for technical solutions that relate […]

IP Strategies for the Newly Released Implementation Regulations of the 4th Amendment of the Chinese Patent Law: Part 3: The 15-Day Mailing Period is Mostly Going Away

2024年2月28日
A Closer Look at the New Presumed Receipt Date Calculation Background China has finally released the long-awaited Patent Law Implementation Regulations (“Regulations”) and associated "Patent Examination Guidelines" (“Guidelines”, similar to the United States' MPEP) which provide further clarity and details of the new Chinese patent law. Today’s article will focus on changes that impact how […]

我們過去活動

Top crossarrow-right