The Spanish Supreme Court takes a stance on the

plausibility of technical effects in patent law

In Judgment 625/2025, the Spanish High Court had the opportunity for the first time in its history to take a position on an issue in patent law that has been long debated, mainly at the level of the European Patent Office (EPO).

First, as is well known, the requirements for patentability are novelty, inventive step, and an accurate description of the invention under analysis to be able to replicate it (industrial application is also included; this requirement is often taken for granted, however, and in 99.99% of cases is not even analyzed). 

This being the case, the plausibility of a technical effect, though not a requirement as such, does influence the patentability of a given invention through either inventive step or sufficiency of the description.

The case analyzed the validity of a specific patent, EP 1427 415, based on the plausibility of the underlying technical effect and the content of the report and common knowledge in this field. 

The crux of the matter, therefore, could be stated as follows: would it be feasible for the technical effect to express itself in light of these teachings/knowledge, or would it be a kind of pipe dream and quasi-unattainable effect (which would result in a purely speculative patent)?

For the purposes of assessing the plausibility in this context, technical data, laboratory tests, and similar evidence from the file are particularly relevant. As such, is it be possible to provide technical data after the priority date to prove such plausibility?

After analyzing the subject matter under debate, the Supreme Court concluded that it is possible to accept the submission of technical evidence and technical data after the priority date to support patentability, provided that the expert in the field does not initially conclude that the invention, or rather the technical effect associated with it, were not at all plausible in light of the application and general knowledge in the sector.

Link to the resolution:click here

February 18, 2026