EPO 2026 Examination Guidelines Enter Force—AI Provisions, Color Drawings, PACE Changes, and New Medical Use Chapter

The European Patent Office’s 2026 Guidelines for Examination under the EPC entered into force on April 1, 2026. The revised guidelines introduce new provisions on the EPO’s use of artificial intelligence, updated procedures for processing color drawings, the abolition of accelerated search under the PACE program, a dedicated new chapter on sufficiency of disclosure for further medical use claims, and the incorporation of two significant Enlarged Board of Appeal decisions—G 1/23 and G 1/24.

The new AI-related guidance addresses how artificial intelligence tools are used within EPO examination processes, establishing a framework for examiners when handling AI-generated content and conducting searches. As generative AI becomes increasingly embedded in professional workflows, major patent offices have begun codifying policies on AI integration into their examination systems. The EPO’s 2026 update makes its approach explicit, aligning with broader trends at patent offices in Japan, the United States, and South Korea, all of which have moved to clarify AI’s role in examination procedures.

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Regarding color drawings, the 2026 Guidelines set out updated procedures in response to the amended Rule 49(11) EPC. Patent applications have traditionally required black-and-white drawings, but the revised guidelines clarify the procedures for applicants to submit color drawings when they are indispensable for an adequate understanding of the invention. This development is particularly relevant for applicants in the life sciences, medical imaging, and display technology sectors, where color information can be integral to disclosing an invention clearly and completely.

On accelerated prosecution, the guidelines abolish accelerated search under the PACE (Patent Prosecution Highway accelerated examination) framework. PACE allows applicants to request expedited examination, but the 2026 revision removes acceleration at the search stage while leaving accelerated examination available. This change will require practitioners to reconsider prosecution timelines when planning entry into the European phase for PCT applications or direct European filings.

A new chapter has been added to address sufficiency of disclosure specifically for further medical use claims. This area of European patent law has long been a source of uncertainty, particularly in pharmaceutical and biotechnology prosecution, where the boundaries between valid second medical use claims and insufficient disclosure are frequently contested. The dedicated chapter provides clearer guidance on what level of experimental evidence must be disclosed to satisfy the sufficiency requirement under Article 83 EPC for these claim types.

The guidelines also incorporate the findings of Enlarged Board of Appeal decisions G 1/23 and G 1/24, both significant precedents affecting procedural and substantive aspects of European patent practice. Integrating these decisions into the formal guidelines text improves consistency of application across examining divisions and appeals.

A structural consolidation accompanies the 2026 revision: content previously distributed across standalone Guides has been merged into the EPC Guidelines and PCT-EPO Guidelines. This reorganization streamlines the reference documents available to applicants and practitioners, reducing the need to consult multiple separate sources. The EPO invited public comments on the revised guidelines through April 3, 2026.

The EPO revises its examination guidelines annually to reflect legislative changes, Enlarged Board decisions, and evolving operational requirements. The 2026 edition stands out for its scope of practical changes—particularly the AI provisions and the abolition of PACE accelerated search—both of which will affect day-to-day prosecution strategy for applicants managing European patent portfolios.