EPO 2026 Examination Guidelines Take Effect: G 1/24 Claim Interpretation, PACE Abolition, and AI Accountability Now Codified

The European Patent Office (EPO) put its 2026 Guidelines for Examination into effect on April 1, superseding the April 2025 editions and integrating two long-standing reference publications—the European Patent Guide and the Euro-PCT Guide—into a single unified document. The former guides remain accessible through May 31, 2026, after which the 2026 Guidelines become the sole authoritative reference. The revisions incorporate two landmark Enlarged Board of Appeal decisions (G 1/24 and G 1/23), abolish the PACE accelerated examination program, introduce the EPO’s first formal guidance on AI use in patent proceedings, and add a new chapter on sufficiency of disclosure for further medical use claims.

The most consequential change is the integration of G 1/24 into EPO examination practice. Under prior practice, examiners consulted the description and drawings primarily when claim language was unclear or ambiguous. The 2026 Guidelines fundamentally change this: examiners must now systematically refer to the description and drawings in all cases, regardless of whether the claim wording appears clear on its face. At the same time, the guidelines explicitly state that the description cannot be used to import limiting features not supported by the claims’ own language. This applies from the search stage onwards.

The practical implications are significant. G 1/24 was designed to harmonize EPO examination practice with that of the Unified Patent Court (UPC), and Solve Intelligence notes that it substantially increases the importance of ensuring internal consistency between claims and description from the earliest filing stage. Applicants who prosecute parallel U.S. and European applications need to be particularly attentive: while U.S. practice has traditionally centered on claim language itself, European practice now more directly constrains claim scope based on specification content.

The second significant change comes from G 1/23, which addresses novelty for selection inventions. The decision establishes that marketed products and their analyzable properties constitute prior art. The 2026 Guidelines reflect this ruling by applying stricter novelty standards to claims that attempt to carve out sub-ranges or specific compounds from earlier disclosures. This change has direct implications for pharmaceutical and chemical patent strategies at the EPO, where selection inventions have historically been a common approach.

A new chapter in Part F of the 2026 Guidelines addresses sufficiency of disclosure for further medical use claims. The chapter introduces additional scrutiny for claims directed to new therapeutic applications of known compounds or compositions, requiring that the specification provide sufficient technical data and evidence to support the asserted therapeutic use. Pharma and biotech applicants will need to ensure their European filings include adequate experimental support from the outset, as post-filing data supplementation at the EPO remains subject to strict limitations.

The 2026 Guidelines also introduce the EPO’s first formal guidance on artificial intelligence use in patent proceedings. The key principle is clear: parties bear full responsibility for AI-assisted filings. Prism News reports that the guidelines explicitly note that “AI is often unable to correctly summarize complex legal topics,” and that practitioners must verify AI-generated EPO proceeding minutes against their own detailed notes. As generative AI tools become increasingly embedded in patent drafting and prosecution workflows, this guidance establishes a clear accountability framework for EPO proceedings.

The abolition of PACE (Programme for Accelerated Prosecution of European Patent Applications) under section E-VIII, 4 of the 2026 Guidelines represents another important operational change. PACE had allowed applicants to request accelerated examination at no cost. With PACE eliminated, applicants seeking faster examination will need to consider the Patent Prosecution Highway (PPH) or other available mechanisms. The practical impact on examination timelines remains to be seen as the new regime takes effect.

The EPO conducted a public consultation on the 2026 Guidelines ahead of their entry into force, with the comment period closing on April 3, 2026. Submitted comments will inform the 2027 guidelines update. Analysis published on Lexology by European IP practitioners notes that the combination of G 1/24 implementation and PACE abolition makes a review of European prosecution strategy a near-term priority for both Japanese and U.S. companies with significant European patent portfolios.

Looking ahead, how G 1/24 is applied in day-to-day examination—and how much variation exists between examiners and technical boards—will be a key question. The alignment with UPC practice is directionally clear, but practical harmonization will take time to establish. The 2027 consultation process will be a further opportunity for practitioners to provide input on any issues arising from the 2026 changes.