The District Court of The Hague rendered a decision on a (successful) insufficiency defense in the proceedings between the Danish company Novozymes and the Dutch company DSM.

In its decision, it is noticeable that the court struggled with the fact that unlike lack of sufficiency, lack of support/clarity is not a ground for revocation of a patent. It stated that the principles of lack of support/clarity and lack of insufficiency are very much related to each other. Subsequently, the court linked up to the sufficiency doctrine to invalidate the patent in suit.

Pursuant to Article 75(1) of the Dutch Patent Act 1995 (DPA) a patent is invalid if the patent specification does not contain a description of the invention which is sufficiently clear and complete to allow a person skilled in the art to work the invention. The provision refers to a "sufficiently clear" description of the invention. However, it must be noted that this refers to clarity of the description of the patent and not to clarity of the terminology used in the patent claims.

Claim 1 of the patent in suit discloses a method of preparing dough comprising the addition of a lipolytic enzyme having activity towards digalactosyl diglyceride and the phospholipid. The phospholipid is not defined in the claim and arguably leaves the reader in doubt as to the meaning of the technical feature to which it refers. The enzyme referred to in the method of claim 1 is defined in terms of a parameter, i.e. having a SLU/LU ratio of at least 3. The SLU/LU ratio is defined in the claim as a ratio of activity towards the C16-C20 acyl bond and C4-C8 acyl bond. According to Novozymes, determining the SLU/LU ratio is the most accurate way to define the enzymatic activity. Novozymes argued that it would be routine for the skilled man to carry out such a test.

The court agreed with DSM that claim 1 of the patent was not defined by way of a chemical formula or an amino acid sequence, which is the common way for defining chemical substances, but merely by way of a functional definition in accordance with the properties of the enzyme. The court further held that Novozymes did not solely claim its selected enzymes, but also the use of all future enzymes which accidentally happened to have the preferred properties, regardless of the fact as to whether the future enzymes are similar to the enzymes described in the patent, and whether they are based on the invention described in the patent. Therefore the court held that claim 1 must be considered to be a "free beer claim"; it claims something everyone would like to have.

The above mentioned, however, cannot separately cause ground for revocation of the patent. The court continued by stating that Article 83 of the European Patent Convention (EPC) requires a patent specification which discloses the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art without undue burden.

The court is of the opinion that the specification of Novozymes' patent is not compliant with Article 83 EPC because the patent specification does not describe the enzymes in terms of their chemical structure or compositions, but merely in terms of their preferred activity without disclosing a technical concept which would teach the man skilled in the art how to put the invention into practice.

The court acknowledges that the sufficiency of the disclosure must be assessed on the basis of the patent application as a whole and not the claims alone, but seems to have taken the lack of clarity of claim 1 into account when assessing the sufficiency of the invention. The court stated that the test described in the patent to select the appropriate enzyme for use in the invention is not enough to meet the sufficiency requirement because the skilled man cannot carry out the invention across the breath of the claim without undue burden.

Unfortunately, the court gave little guidance as to why the test would put an undue burden on the skilled man. The court only stated that there are a lot of enzymes which need to be tested to carry out the invention. It remains vague, however, under what circumstances a test would cause an undue burden.