Supreme Court Decision of April 24, 2025, Teva (ECLI:ES:TS:2025:1714)
1. Facts
The litigation pits the pharmaceutical company Teva against the holder of a European patent relating to a compound intended for the treatment of inflammatory diseases. Teva sought partial invalidation of the patent on the grounds of lack of inventive step, arguing that the claimed technical effect was not plausible in light of the information contained in the original application. The defendant argued that the plausibility of the effect was evident from the general knowledge of a person skilled in the art and from subsequent studies confirming the compound’s efficacy.
After proceeding through the trial and appellate courts, the case reached the Supreme Court, which was tasked with determining whether the plausibility of the intended technical effect constitutes a required criterion for assessing inventive step under the Patent Law (LP) and the European Patent Convention (EPC).
2. Statements
The Supreme Court proceeds from the principle that inventive step must be assessed in accordance with Article 56 of the Spanish Patent Code and the established case law of the European Patent Office (EPO). It emphasizes that the invention must provide a technical solution to an objective technical problem, and that the claimed contribution must be credible at the time of filing.
The Board adopts the concept of“plausibility of the technical effect,”as developed in EPO case law, according to which a mere assertion of the technical effect is not sufficient: based on the application and the general knowledge of a person skilled in the art, the effect must be plausible or reasonably supported. If the effect is not plausible at that point, the invention lacks an inventive step.
The Supreme Court clarifies that plausibility does not constitute a new, independent requirement for patentability, but rather a methodological criterion for assessing inventive step. It rejects the idea that subsequent evidence or data may be used to remedy an initial lack of plausibility, as this would upset the balance of the patent system and unduly expand the scope of the original application.
Applying this doctrine to the case, the Supreme Court concludes that the contested patent did not provide sufficient data to substantiate the alleged anti-inflammatory effect. The description did not contain experimental examples or specific references that would allow an expert to consider the compound’s mechanism of action plausible. Consequently, it upholds the partial invalidation of the patent for lack of inventive step.
3. Comment
The Supreme Court’s ruling consolidates in Spain the European doctrine regarding the plausibility of the technical effect as an essential element for assessing inventive step. The Chamber adopts the case law of the EPO and the CJEU, establishing that the applicant must provide, at the time of filing, a sufficient technical basis to make the invention’s effectiveness credible. This prevents the granting of speculative patents or those based on mere hypotheses.
In practice, this requires companies to justify their inventions more rigorously, providing data or references that support the plausibility of the claimed effect.
Ana Sanz, Associate Partnerin the Legal Department.