In T 2030/20, the board dealt with the interpretation of the terms “immersion tube” in claim 1 in the context of novelty assessment.

The patent proprietor wanted the term “immersion tube” in claim 1 of the granted patent to be understood in the narrower sense of the direct literal meaning, according to which the tube should be suitable for immersion in a culture medium. Accordingly, a dip tube must in particular be long enough to be able to reach the culture medium, for example a liquid such as the culture broth or a gel, of a connected disposable bioreactor.

The board noted that, according to settled case law, the terms used in a patent must be given the meaning customary in the relevant prior art, unless a special meaning was assigned to them in the description of the patent (see Case Law of the Boards of Appeal, 10th edition 2022, Chapter II.A.6.3.3; see also T 1473/19). If the latter is the case, this can also lead to a claim feature being given a broader meaning in the light of the description compared to the usual meaning in the relevant prior art. This is the case here.

It is true that according to the embodiments of the patent shown in the figures, as explained by the patent proprietor, it is preferred that an immersion tube of the patent is intended to be immersed in a culture broth present in the bioreactor as intended. However, the patent gives the term “immersion tube” in the description a broader meaning that goes beyond the actual meaning of the word, according to which an immersion tube can only project into the reaction chamber, i.e. it can end anywhere within the reaction chamber above the liquid level.

The amendments made in auxiliary request 1 concerned the description of the dip tubes in paragraphs 46 and 60. However, the board was of the opinion that the unchanged paragraphs of the patent specification continued to define that the dip tubes within the meaning of the patent merely had to be long enough to extend into the reaction space.

An unadapted description may thus imply a broader meaning of features of a claim, so that relevant prior art not showing the features in the narrow sense of the claim could become novelty-destroying.