T 0847/24 – New EPO Case Law Informs Strategy for AI-Assisted Engineering Design Patents

The recent EPO Board of Appeal decision T 0847/24 sets out that, when AI is involved in product design, the patent claims should follow the process through from digital model to manufactured reality if that is the invention to be protected.

It was ruled that a patentee could not, after grant, add a manufacturing step to a claim that had originally been directed only to a computer-implemented method for generating configuration data for a customised implant. The Board found that such an amendment violates Article 123(3) EPC, because it extends the scope of protection conferred by the granted patent.

Whilst the substance of the case related to a Medtech invention, the Board’s reasoning is directly relevant to the growing field of AI-assisted engineering design and modelling. For example, tools that generate cooling and power layouts for data centres, optimise geometries for automotive or aerospace components, produce manufacturing-ready CAD/CAM files for 3D-printed parts, or configure industrial equipment for a particular installation all make use of innovative algorithms for product design.

T 0847/24 confirms that at the EPO, modelling data representing a product, and the manufacture of the physical product using the modelling data, are not the same invention, and post-grant amendment cannot quietly convert one into the other.

What Actually Happened in the Case

The patent at issue,  EP2931143, covered a computer-implemented method that takes patient-specific or design parameters and generates configuration data for a customised implant. As granted, the claim was limited to that computational step of generating data representing the configured implant, and not the implant itself.

During opposition, the patentee (Materialise NV) added an explicit step of manufacturing the implant according to the generated data configuration. Tying the claim more closely to production seemed, on its face, to be a narrowing amendment that would also provide an inventive step.

The Board disagreed, and the reasoning is the part that matters for AI innovators.

Article 64(2) EPC provides that where a European patent claims a process, the protection conferred extends to products directly obtained by that process. In their decision, the Board took the view that the word “directly” excludes scenarios where further steps are required to instantiate the product:

The Board understands this to mean that the protection conferred by a process claim does not, as a rule, extend to products obtained only by carrying out further steps which are neither defined in that claim nor implied by it. (Reasons for Decision, 6.4.2)

Applying this to the patent in suit, the Board concluded that independent claim 1 defined a process in which only data was “directly” obtained, and that further, unclaimed steps were required to manufacture an implant using said data. The independent claim did not define a set of manufacturing process steps, so the physical implant was never a “product directly obtained” by the claimed process in the sense of Article 64(2) EPC. The later attempt to add manufacture of the implant as a claim feature therefore extended the protection conferred by the patent and was not allowable under Article 123(3) EPC.

Why This Matters to AI Innovators

Strip out the word “implant” and replace it with almost any AI-generated engineering product, and the importance of the decision becomes apparent to anyone drafting patents around generative or AI-assisted design.

There are two candidate inventions in the AI context: the method of generating the digital representation (the AI/optimisation process), and the physical object or system that eventually gets built from it. Commercially, the entity worth suing for infringement is often the one manufacturing or deploying the physical result, and not the one running the design software. T 0847/24 tells us, in plain terms, that the EPO will not let a patentee bridge that gap after the fact by bolting on a manufacturing step to a claim that was granted purely as a data-generating method. Article 64(2) EPC is not a backdoor for retroactively expanding a software claim into a product claim.

This matters more for AI-generated designs than for conventional engineering patents, for a structural reason. It is a common strategy in drafting AI patents to claim, as the invention, the output of the model, such as the optimisation, the configuration, or the generated geometry. Often this is where the algorithmic novelty and inventive step genuinely reside. T 0847/24 confirms that this practice should be revised. If the physical implementation is where the commercial value and the infringement exposure actually sit, failing to claim it directly leaves a gap that cannot be patched up at the opposition or amendment stage.

Drafting Lessons: Claim the Whole Digital-to-Physical Lifecycle

The clearest takeaways from T 0847/24 are:

1. A newly drafted patent application should include, where supported, claims to the physical product itself and to an explicit manufacturing or fabrication process, so that Article 64(2) EPC protection arises from the granted claim set rather than from an attempted post-grant amendment.
2. Related to this, Applicants should decide at filing what commercial conduct they will likely need to stop: if the target is manufacture or deployment of a physical product, a claim limited to generating design or configuration data may be insufficient.
3. For existing patents, patentees should treat later “upgrade” amendments from data-generation to manufacture as high risk, because T 0847/24 shows that the EPO is unlikely to permit a software/design claim to be converted after grant into protection for downstream physical products.

This article was prepared by Senior European Patent Attorney, Gearoid Moran.