A manifest preparation of a product may already be at hand if the product shows the characteristics mentioned in the patent claim and is geared towards a use in which achieving the patented intended use (here: avoidance of cancer risks) is deemed necessary. In such case, no further manifestation of the designation for the claimed use (for example, by means of instructions for use) is required for finding infringement of a use patent by way of manifest preparation.

In case of use patents, patent protection is shifted, covering not only the protected use as such but also previous activities by which the product is “manifestly prepared” for the claimed use. For a manifest preparation, the product must be geared towards the claimed use so that it is obvious for the customer that the product is intended to be used as claimed in the patent. This can, for example, be achieved by a particular composition of the product so that it is predestined for the claimed use, or by instructions for use accompanying the product upon sale.

In the case at hand, the plaintiff was the owner of the European Patent 0 399 320 B2 (“patent-in-suit”) concerning glass fibres with increased biological compatibility. Claim 1 of the patent-in-suit refers to the use of glass fibres with a specific composition and diameter as glass fibres which exhibit no carcinogenic potential. The defendants produced in Belgium and distributed in Germany fibre glass products (“attacked embodiments”) with the claimed composition and diameter to the building materials trade where the attacked embodiments could be purchased by customers for use as insulating material in building construction.

The plaintiff filed an infringement complaint against the defendants with the Mannheim District Court asserting literal infringement of claim 1 of the patent-in-suit and requesting that the defendants were, in principle, obliged to pay damages for the infringement of the patent-in-suit and requesting that the defendants be adjudged to render accounts. The Mannheim District Court allowed the complaint.

In the appeal proceedings, the Karlsruhe Appeal Court dismissed the appeal filed by the defendants and confirmed the first instance judgment.

The Karlsruhe Appeal Court held that the attacked embodiments were manifestly prepared as they were designed and distributed as insulating material in building construction, i.e. for a purpose in which the risk of cancer should be excluded with sufficient certainty according to the applicable employment protection provisions. In this case, no explicit hint towards the lacking of a carcinogenic potential (lacking of which being prescribed by law) was required for manifestly preparing the product for the claimed use.

By offering the attacked embodiments as insulating material for building construction, the offering person incidentally stated that the offered product met the requirements of the applicable employment protection provisions.

The actual carcinogenic potential of the attacked embodiments was, according to the Karlsruhe Appeal Court, irrelevant. It was only decisive that the product had the claimed geometric and chemical characteristics and was manifestly prepared for the claimed use.


With the present decision, the Karlsruhe Appeal Court confirms the generally accepted principles regarding the manifest preparation in case of use patents (cf. e.g. German Federal Supreme Court GRUR 1990, 505 – Geschlitzte Abdeckfolie/Slotted Cover Foils). At the same time, the Karlsruhe Appeal Court clarifies the prerequisites of such manifest preparation. In case the product has the characteristics mentioned in the patent claim and in case achieving the claimed intended use is deemed necessary, a manifest preparation may be assumed, without further manifestation of the designation of the product for the claimed use being required.

Yet, since the Karlsruhe Appeal Court found that it was not absolutely clarified in the German case law what requirements are to be imposed on the manifest preparation of a product for a patented use, it admitted an appeal on points of law to the German Federal Supreme Court. It remains to be seen whether the Supreme Court provides additional desirable clarification in this regard.