After conclusion of patent infringement proceedings by court decision, at least one party has to speculate about the scope of the court’s ruling. If infringement is confirmed, the defendant needs to know to which extent his product must be altered so that it is no longer covered by the injunction. In case of a dismissal the plaintiff will ponder whether the judgment applies to the entire assortment of the defendant’s products or only to single articles specifically dealt with in the proceedings. In the latter case the option of a new attack would remain, possibly before another court.

The former Reichsgericht had been confronted with this problem alrea. It used a simple formula, according to which an injunction covers products with only minor changes over the originally attacked article (RG, decision of 15/11/1937 – I 102/37). In a later decision, the Court of Appeals of Düsseldorf has ruled that the test should be to ask whether deviation between the products is so insignificant, that there cannot be any serious dispute about their equality (OLG Düsseldorf, order of 9/1/2006 – I-2 W 36/05).

The Federal Court of Justice (BGH) has now attempted to establish more tangible criteria (judgment of 21/2/2012 – X ZR 111/09 – Rohrreinigungsdüse II). It held that, in the first place, the factual allegations which the plaintiff submitted to demonstrate that the attacked product falls under a patent claim is decisive. If these allegations apply identically to another article, such article is also covered by the court decision.

It is yet to be seen if such criteria a really tangible. This will primarily depend on the degree of substantiation of the plaintiff’s submissions in the prior infringement proceedings. Future plaintiffs are advised to clarify for every element of the patent claim whether he regards it to be fulfilled by the concrete design of the product under dispute (e. g. by reference to a drawing or photograph) or, more broadly, by a generalized design aspect implemented with the product (e. g. “obtuse angle” instead of “100°”). If such a generalization is made, such a broadened injunction will further require a certain risk of future infringements in this generalized extent, as the BGH remarked.