In the case of Human t-PA/Genentech an EPO Technical Board of Appeal dealt with two key issues relating to protection of inventions relating to genetic engineering. The first was the question of what disclosure is required to support a claim to a specific amino acid sequence. The second was how precisely must the functions of a material which is defined in functional terms themselves be defined.

The first issue came up in connection with the question of whether a claim that specified a particular amino acid sequence for a polypeptide was entitled to the priority date of an application that described what was said to be the same material but which had as a result of sequencing errors identified some of the amino acids in the sequence differently. The Board held that the structure of the polypeptide was one of its essential characteristics, particularly in view of the fact that changing only one or two amino acids could change its properties. Consequently, even though the priority application had described a method of producing the polypeptide, a claim directed to that polypeptide as such and characterized by the amino acid sequence in question was not entitled to that priority date.

The second issue came up in the context of a claim reading as follows:

In dealing with this claim, the Board first had to consider whether an objection could be taken in opposition proceedings that the claims lacked clarity and were unsupported by the disclosure. The grounds under which oppositions can be made are set out in Article 100 of the European Patent Convention and do not specifically include lack of clarity and undue breadth, although under Article 84, both of these grounds can be relied upon by the Examining division during initial examination of the application. In the present case, the Board concluded that since the wording in question arose from an amendment offered by the patentee, it did have jurisdiction to consider whether the amended claims met the requirements of Article 84 (the unexpressed reason apparently being that one should not be allowed to secure by amendment after grant what one could not have secured before grant in normal prosecution). Once this was done, the Board had no trouble in finding that the term "having human tissue plasminogen function" was vague and ambiguous. The Board commented, "Human t-PA is a molecule with multiple functions, some of which are in common with other molecules ...Therefore a reference which fails to characterize the precise functions meant is of no assistance to the skilled addressee." The claim was therefore both insufficient and lacking in clarity.

The lesson of this case may be therefore that when dealing with inventions in this area of technology one should be careful to ensure that sequences set out in a specification are correct, give as clear a set of general instructions as possible as to how to produce the desired product in case one is forced to rely on product-by-process protection and make absolutely clear what functions one is referring to when attempting to define a product by its function.

Editor's note: See the related discussions in our March 1999 Newsletter (N.S. 190), in our August 1999 Newsletter (N.S. 191) and in our June 2000 Newsletter (N.S. 192).