Netherlands: Supreme Court rules on role of description in claim interpretation

Managing IP is part of Legal Benchmarking Limited, 1-2 Paris Gardens, London, SE1 8ND

Copyright © Legal Benchmarking Limited and its affiliated companies 2026

Accessibility | Terms of Use | Privacy Policy | Modern Slavery Statement

Netherlands: Supreme Court rules on role of description in claim interpretation

Resolution Chemicals v AstraZeneca B.V. and Shionogi (Supreme Court of The Netherlands, The Hague, June 8 2018) deals with the extent of protection that is conferred by patent EP0521471 (EP 471), for rosuvastatin, a new cholesterol inhibitor.

Claim 1 of EP 471 does not claim the active ingredient of rosuvastatin (i.e. the rosuvastatin anion), but "the compound [rosuvastatin, described using its molecular formula] acid or a non-toxic pharmaceutically acceptable salt thereof''.

Resolution took the position that the feature "or a non-toxic pharmaceutically acceptable salt thereof" in claim 1 must be interpreted to only comprise the salts mentioned in paragraph [0007] of the patent, stating that "the term "a non-toxic pharmaceutically acceptable salt" refers to a salt in which the cation is an alkali metal ion, an alkaline earth metal ion, or an ammonium ion". Hence, claim 1 must be interpreted more strictly than the literal claim wording gives rise to, and rosuvastatin zinc is outside the scope.

AstraZeneca argued that the average skilled person, taking into account his general professional knowledge, would take paragraph [0007] to merely provide a non-exhaustive list of suitable salts, and that "a non-toxic pharmaceutically acceptable salt" should be understood to include the zinc salt.

The district court concluded that the skilled person would presume that the list of salts in paragraph [0007] was a conscious choice by the patentee and thus construe this paragraph as a limiting definition. It therefore ruled that the zinc salt was not within the scope of EP 471.

The Court of Appeal reversed this decision, and ruled that the average skilled person would have understood that the inventive idea does not reside in identifying suitable salt forms, but in providing a new cholesterol inhibitor having a better biological activity than existing compounds. Accordingly, he would not interpret the patent to "waive'' protection for salts of rosuvastatin other than those mentioned in [0007].

The Supreme Court rejected Resolution's complaint that the Court of Appeal had given more weight to the "essence of the invention'' than what is written in the description and affirmed the Court of Appeal's decision, indicating that it explained the patent claims in light of the common general knowledge of the average skilled person. In addition to this, it also addressed the contribution of rosuvastatin to the art, the role of salt forms in a pharmaceutical rosuvastatin composition, and the fact that EP 471 as a compound patent conferred absolute product protection. It further indicated that, when finding a fair balance according to the Protocol to Article 69 of the European Patent Convention, weight must be given to the skilled person's opinion on whether there are valid reasons for a limitation of the scope of protection. This decision indicates that the waiver doctrine as formulated in the Van Bentum v Kool decision of 2002 no longer has an independent significance as a separate test.

tepper.jpg

Annemiek Tepper


V.O.Carnegieplein 5, 2517 KJThe HagueThe NetherlandsTel: +31 70 416 67 11Fax: +31 70 416 67 99info@vo.euwww.vo.eu

more from across site and SHARED ros bottom lb

More from across our site

As the US reflects on 250 years of independence, patent lawyers say innovation is reshaping old hiring priorities, with firms seeking broader IP expertise over specialisation
The Nokia v Acer ruling in the UK suggests arbitration is moving from the sidelines towards the mainstream of global FRAND disputes - and could reshape forum strategy in the process
The Life Sciences Awards is thrilled to present the shortlist for the 2026 Americas Awards
From Türkiye to Poland and Nigeria, firms with deep local roots continue to dominate the top tier, proving that market expertise can outweigh international scale in many CEE, Middle Eastern and African jurisdictions
Former Hoyng Rokh partner Simon Dack takes a leading PMAC role as busy firms continue to jostle for position
Franck Fougere, founder and managing partner of Ananda IP in Thailand, describes how the firm has developed a reputation for patent work and why he believes IP practice is set to change
After two decades at Kass International, Geetha Kandiah discusses the lessons that shaped her career, building an inclusive regional firm, and AI opportunities
Manisha Singh of LexOrbis discusses the need for commercial alignment with clients and why IP lawyers need to have curiosity at their core
As firms expand into integrated IP services, recent hires show the model's appeal – but high-profile departures reveal how quickly questions of depth and durability can emerge
In-house counsel say private practice firms either aren’t conveying sustainability messaging or simply ‘don’t care’, but a mindful approach to the topic could swing pitches
Gift this article