1.3.2 Request to cease alleged infringement and institution of proceedings for non-infringement – Article 105(1)(b) EPC

In T 195/93 the board held that if a patentee simply sent a legal warning letter asking the intervener to stop production and sale of a product covered by the patent, this could not be regarded as institution of proceedings for a court ruling even if under national law the addressee became liable for damages 30 days after receiving the letter. The intervention was therefore rejected as inadmissible.

According to T 392/97, Art. 105 EPC 1973 required that an intervener should prove both that the patentee had requested that he cease alleged infringement of the patent and that he had instituted proceedings for a court ruling that he was not infringing the patent. Thus where the letter was sent not to the allegedly infringing company, but to an unrelated one which it was assumed was about to acquire it, the first requirement was not fulfilled and their interventions were inadmissible. The first requirement was also not fulfilled in T 446/95, where the letter merely set out a position adopted in response to a letter from the purported intervener, and did not give notice to cease infringement. According to T 887/04 of 14 November 2006 date: 2006-11-14, it was for the assumed infringer to prove, first, that he had received a "request" to cease the infringement, i.e. that he had been expressly asked to do so, and, second, that he had been required to "cease", i.e. put an end to, the infringement. Proof of mere warnings or threats of legal action had therefore to be considered insufficient.

In T 898/07 the board found the intervention admissible. It was apparent from the documents submitted by the opponent that the respondent had repeatedly informed it that it considered its actions to infringe the patent and, with reference to infringement proceedings already pending against third parties, invited it to enter licensing negotiations. The board considered this a request to cease patent infringement by concluding a licensing agreement which would render the allegedly unlawful conduct (patent infringement) lawful (licensed use). This met the first requirement under Art. 105(1)(b) EPC, the wording of which covered not only to a request to refrain from using the invention altogether, but also generally to a request to cease the alleged patent infringement. In addition, the opponent had instituted proceedings against the respondent for a declaration of non-infringement of the patent.

In T 1138/11 the board held that compliance with the requirement that the intervener has been requested to cease the alleged patent infringement was not to be determined in accordance with the relevant national law. Since the laws in the contracting states varied to quite an extent from one to another, this requirement had to be applied in a harmonised manner for all contracting states. This could only be achieved by way of an autonomous interpretation of the EPC provisions and their legal terms. The board also found that, since an intervention by a third party was treated as an opposition and so – as an exception to the 9-month time limit for filing a notice of opposition – this party was granted the status of an opponent, Art. 105 EPC had to be interpreted in a restrictive manner.

In T 304/17 the appellant argued that for the three-month time limit to be triggered, it was necessary but also sufficient for the two criteria mentioned in Art. 105(1)(b) EPC to be fulfilled, regardless of the order in which this happened. The board disagreed with this understanding of Art. 105(1)(b) EPC. It followed from its clear wording that it required a specific sequence of events ("following a request of the proprietor of the patent ..., the third party has instituted proceedings ..."). The travaux préparatoires confirmed that the legislator had intentionally chosen this sequence of events. This conclusion was also in line with a systematic interpretation, because in both alternative scenarios – Art. 105(1)(a) and (b) EPC – it was the formal institution of proceedings (before a court or another competent national authority) which triggered the time limit. These were events which could be unambiguously established with legal certainty, since they had official dates (see T 296/93) and thus set "a clear demarcation line" (see also T 18/98).