The 2026 EPO Guidelines: Five Changes Every Patent Applicant Should Know.

The European Patent Office (EPO) updates its Guidelines for Examination every year, but the 2026 edition is more than a routine update. It reflects important decisions of the Enlarged Board of Appeal and provides applicants with greater clarity on the examination of European patent applications.

Whether you are filing your first European patent application or managing an established international patent portfolio, understanding these developments can help you develop a more effective patent strategy and avoid potential pitfalls during examination.

Here are five of the most important changes.

1. The Role of the Description Has Been Clarified

One of the biggest changes follows the Enlarged Board's decision in G 1/24. The Guidelines now confirm that, when assessing patentability, examiners should always interpret the claims in light of the description and drawings.

For many applicants, this means the description is no longer viewed simply as supporting material accompanying the claims. Instead, it forms an integral part of how the invention is interpreted throughout examination and, potentially, in later opposition proceedings.

Practical example

Imagine a medical device company files claims directed to a "flexible catheter". Throughout the description, however, every embodiment explains that flexibility is achieved using a particular braided reinforcement.

During examination or opposition proceedings, the description may influence how the term "flexible catheter" is interpreted, particularly where its meaning is disputed.

The lesson is straightforward: claims and descriptions should work together. Inconsistencies that once appeared harmless may now become significant.

2. Selection Inventions May Be Easier to Defend

Many pharmaceutical, biotechnology and chemical inventions involve selecting something specific from a broader known group, for example, identifying a particularly effective dosage, concentration, temperature range or chemical compound.

The 2026 Guidelines simplify the assessment of novelty for so-called "selection inventions". Rather than applying a series of judicially developed tests that have evolved over many years, the key question is now much simpler: does the prior art directly and unambiguously disclose the claimed selection?

Practical example

Suppose previous research discloses an antibody dosage between 1 mg and 100 mg.

Your clinical studies demonstrate that a dosage of 12-18 mg produces unexpectedly improved efficacy with fewer adverse effects.

Under the revised approach, the key issue is whether the earlier publication clearly disclosed that narrower dosage range, not whether it might theoretically have been selected.

For companies developing improved formulations or optimised treatment regimens, this provides a clearer framework for assessing patentability.

3. Competitors' Products Can Count as Prior Art

Another important update reflects the Enlarged Board's decision in G 1/23.

If a competitor has already sold a product commercially, the product itself, and any characteristics that can be analysed by a skilled person, may form part of the prior art.

This is true even if the manufacturing process cannot be reproduced.

Practical example

A materials company launches a new polymer with exceptional thermal stability.

Although the manufacturing method remains confidential, competitors purchase samples and analyse the polymer's composition using standard analytical techniques.

Those analysable properties may now be relied upon during patent examination.

For innovative businesses, this highlights the importance of filing patent applications before products are released commercially.

4. The EPO Is Providing Greater Clarity on Amendments

Most European patent applications are amended during examination.

The updated Guidelines provide clearer guidance on when examiners should admit amended claims and additional requests, and when they should explain why amendments are being refused.

While this may sound procedural, it can have a real impact on prosecution strategy.

Practical example

An applicant receives an inventive-step objection during examination and responds by filing amended claims that address the examiner's concerns.

Under the revised Guidelines, examining divisions are expected to provide clearer reasons when deciding whether to admit those amendments into the proceedings. This should give applicants a better understanding of why particular amendments are accepted or refused and help them make more informed decisions about how to progress their application.

While every case will depend on its individual facts, the updated approach aims to improve the transparency and predictability of examination proceedings.

5. Artificial Intelligence Can Help, But Human Oversight Remains Essential

Artificial intelligence is rapidly becoming part of everyday patent practice.

Many inventors now use AI to summarise technical papers, prepare invention disclosures or generate first drafts of patent specifications.

The EPO recognises this trend. However, the 2026 Guidelines make one point very clearly: responsibility always remains with the applicant and their representative.

Practical example

A start-up uses a generative AI tool to prepare an initial patent application describing a new machine-learning algorithm.

The draft appears comprehensive, but it inadvertently introduces technical features that were never part of the original invention and omits several essential implementation details.

If those errors remain in the application, they may later create problems relating to sufficiency, clarity or added subject-matter.

AI can significantly improve efficiency, but it is not a substitute for careful legal and technical review.

What Does This Mean for Patent Applicants?

The practical message from the 2026 Guidelines is that successful patents begin long before examination starts.

Applicants should consider:

• ensuring that claims and descriptions are drafted consistently from the outset;
• carrying out appropriate prior art searches, including reviewing commercially available competitor products before filing;
• clearly documenting the technical basis for selected features, such as dosage ranges, parameter ranges or formulations, where relevant;
• developing a considered amendment strategy early in prosecution rather than waiting until objections become more difficult to overcome; and
• ensuring that, where AI is used to assist with preparing patent applications, all documents are carefully reviewed by a patent professional before filing.

Looking Ahead

The European patent landscape continues to evolve, and even seemingly small changes in examination practice can have a significant impact on the scope, strength and enforceability of your patent rights. Keeping up to date with these developments is essential to building and maintaining a valuable patent portfolio.

If you would like to discuss how the 2026 EPO Guidelines may affect your patent portfolio or a specific application, please contact our patent team. We would be delighted to advise on European and international filing strategies, patent prosecution and portfolio management.