Germany: The underrated alternative ground

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

Germany: The underrated alternative ground

In European patent opposition practice most opposition cases are based on the ground of a lack of novelty or at least on the lack of an inventive step. The success of these opposition cases strongly depends on the quality of the prior art documents cited by the opponent.

However, Article 100 EPC also provides the opponent with the opportunity to base an opposition on the argument that the subject matter of the European patent extends beyond the content of the application as filed or on the ground of insufficient disclosure. The latter opposition ground is used relatively seldom – but why?

Certainly, a patent practitioner who drafts a patent application usually knows which technical details are important to meet the requirement of sufficient disclosure. However, in this regard there are some peculiarities to consider.

Chapter F-IV, 6.4 of the Guidelines for Examination explains the relationship between Article 83 EPC (insufficient disclosure) versus Article 84 EPC (lack of support). Both requirements are designed to reflect the principle that the terms of a claim should be commensurate with, or be justified by, the invention's technical contribution to the prior art. The reasons for failure to meet the requirements of Article 84 EPC may in effect be the same as those that led to the infringement of Article 83 EPC, namely that the invention, over the whole range claimed, extends to technical subject matter that is not made available to the person skilled in the art by the application as filed.

The difference is that a problem with Article 84 EPC may be overcome by the technical knowledge of a person skilled in the art. Whether an objection is raised on the ground of a lack of support or insufficiency of disclosure is relatively unimportant in examination proceedings, but important in opposition proceedings, since in those only the latter argument is available.

In decision T 1545/13 the Boards of Appeal defines a methodical approach, to find out whether there is insufficient disclosure: "For making a case of insufficiency of disclosure, it is necessary to identify gaps in information resulting either from limitations in teaching or a lack of guidance in general, or a lack in guidance in case of failures, or the impossibility to verify parameters, or purpose-related instructions or the absence of criteria or selection rules. The board has therefore to decide whether the patent in suit suffers from such critical gaps in information or a lack of guidance. The question then has to be answered whether the skilled person with his common general knowledge can remedy these defects, or whether the consequences of the information gaps would result in an excessive number of experiments ('undue burden' or 'research programme')".

The case underlying the more recent unpublished decision T 0526/14 gives a lucid example of how to use this methodical approach. The question was whether a technical feature of the independent claim 1 had been sufficiently disclosed. Claim 1 relates to a single-portion capsule for an espresso coffee machine, comprising a capsule base with a through-passage which is suitable for preventing a hydraulic build-up of pressure when brewing the coffee held in the capsule.

It was therefore necessary to assess whether that feature and the supporting description disclosed the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art. In the description or drawings there was no additional information available as to how to design the said through-passage in order to prevent a hydraulic build-up of pressure. That gap in information due to the absence of relevant criteria cannot be overcome by a skilled person with only common general knowledge. The reason is that several technical and physical parameters influence the build up of pressure inside the capsule, such as the design of the capsule and its volume, the injection rate of the hot water being introduced and the absorbability of the coffee powder. None of this information is available in the description. The description should at least have explained these relevant influences using concrete examples with parameter information in order to fulfil the requirement of sufficient disclosure in accordance with Article 83 EPC. In consequence, the patent has been revoked due to insufficient disclosure.

For European oppositions it is worth verifying whether insufficient disclosure is promising as a ground for opposition, using the methodical approach set forth by the previously discussed case law.

Lutz Kietzmann


Maiwald Patentanwalts GmbHElisenhof, Elisenstr 3D-80335, Munich, GermanyTel: +49 89 74 72 660 Fax: +49 89 77 64 24info@maiwald.euwww.maiwald.eu

more from across site and SHARED ros bottom lb

More from across our site

Sheppard has added quantum and robotics expertise to its AI industry team to help clients navigate questions around inventorship and IP infringement
The 2026 Americas ceremony recognised outstanding firms and practitioners, along with highlighting impact cases of the year
A development concerning Stephen Thaler’s AI copyright application in India and an integration between IPH group firms were also among the top talking points
As concerns around the little-known litigation tool increase, practitioners say they are educating their clients on how it can be most effective
Kilburn & Strode and Mewburn Ellis are just two firms that have invested heavily in office space – a sign that the legal industry is serious about in-person working
In major recent developments, Dyson snagged another win against Hong Kong-based competitor Dreame and a new AI-powered UPC platform was launched
Mohit and Sidhant Goel decided not to pursue an interim injunction application so that their client, Communications Components Antenna, could benefit from a fast-track trial
Anita Cade, head of Ashurst’s IP and media team in Australia, discusses why law firms that can pull together capability across different practice areas and jurisdictions stand to gain
INTA’s CEO says London-based firms have registered fewer delegates compared to past meetings in San Diego and Atlanta, and questions the 'ethics' of trying to participate without registering
Lobbies and interest groups are among the interveners in a major dispute over whether courts can set patent pool rates
Gift this article