6.3.1 General principles

Catchword: 

1. On the limits of claim interpretation in the light of the description (see point 13 of the reasons).  2. In application of decision G 3/14, an objection under Article 84 EPC that a claim is not supported by the description is open to examination in opposition or opposition appeal proceedings only when, and then only to the extent that, the lack of support has been introduced by an amendment to the patent. It must thus be accepted that the removal of an inconsistency between the description and a claim amended in opposition or opposition appeal proceedings is not possible when the inconsistency previously existed in the patent as granted (see point 83 of the reasons).

Catchword: 

With regard to the question of compatibility of certain principles of claim interpretation for the purposes of considering novelty or inventive step with Article 69 EPC, reference is made to Reasons 1.1.11 to 1.1.16.  The principle of primacy of the claims seems to exclude the use of the description and drawings for limiting the claims if an interpretation of the claim in the light of common general knowledge already leads to a technically meaningful result. Similarly, the principle, established by case law, according to which "limiting features which are only present in the description and not in the claim cannot be read into a patent claim" is also fully compatible with Article 69 EPC and Article 1 of the Protocol.

Abstract

In T 177/22 the board stated that in order to assess whether the claimed invention is sufficiently disclosed or is novel or inventive, the claimed invention must – to the extent to which this is decisive for the outcome of the case – first be determined by interpreting the claim from the perspective of the person skilled in the art (see T 367/20). When doing this, a board of appeal is not limited to the claim interpretations advanced by the parties but may also adopt a claim interpretation of its own (T 450/20, T 1537/21).

According to the board, the relevant feature of claim 1 as granted was to be interpreted not only in the context of the other features in that claim but also in the context of the description as granted (for recent case law on this matter see T 367/20, referring to the principles of claim interpretation as set out in Art. 69 EPC and Art. 1 of the Protocol on the Interpretation of Article 69 EPC; T 447/22, referring to the general principle under the EPC that claims can be interpreted only in context, which includes the description and the drawings; T 1473/19, referring to G 2/88, applying Art. 69 EPC and the Protocol for interpreting "the technical features of the claim" when assessing extension of the scope of protection under Art. 123(3) EPC; G 6/88 (taken on the same day as G 2/88), where the Enlarged Board (directly) applied Art. 69 EPC and the Protocol "to construe the claim in order to determine its technical features" when assessing novelty; compare also Court of Appeal of the Unified Patent Court, UPC_CoA_335/2023, Grounds 4.d)aa), referring to Art. 69 EPC and the Protocol as well as to G 2/88, and stating that the principles for the interpretation of a patent claim apply equally to the assessment of the infringement and the validity of a European patent; as to the harmonised approach on claim interpretation introduced by the EPC see further G 6/88, referring to Art. 69 EPC and the Protocol on its interpretation as "a mechanism for harmonisation" which provides a "method of interpretation of claims of European patents throughout their life"; T 1473/19, referring to the legitimate interests of the users of the European patent system in a common approach to claim interpretation; T 367/20 and T 438/22, referring to the overarching objective under the EPC that authorities, courts and the public interpreting the claims should, as far as possible, arrive at the same understanding of the claimed subject-matter as the EPO bodies deciding on its patentability; as to the primacy of the claims under Art. 69 EPC and the Protocol see T 1473/19; in regard to the latter compare also Court of Appeal of the Unified Patent Court, UPC_CoA_335/2023, Grounds 4.d)aa), referring to the patent claim as not only the starting point, but the decisive basis for determining its subject-matter and scope of protection).

The board noted that the fact that the patent specification disclosed embodiments which were not encompassed by claim 1 did not result in an insufficient disclosure but in a lack of support by the description under Art. 84 EPC. However, the requirements of Art. 84 EPC play no role in opposition proceedings where the proprietor seeks to have the patent as granted upheld (G 3/14, point 55 of the Reasons).

The respondent (opponent) submitted that a different, broader, claim interpretation had to be adopted for the assessment of novelty and inventive step than for the assessment of sufficiency of disclosure. The board disagreed and stated that the "invention" within the meaning of Art. 54(1) EPC, the "invention" within the meaning of Art. 56 EPC and the "invention" within the meaning of Art. 100(b) EPC (and Art. 83 EPC) all refer to the claimed subject-matter (see T 1473/19 and T 92/21), and a given patent claim's subject-matter must be interpreted and determined in a uniform and consistent manner (see T 1473/19). This excluded interpreting the same claim differently when assessing sufficiency of disclosure on the one hand, and when assessing novelty and inventive step on the other hand. It also presupposed that the same principles of claim interpretation must be applied when assessing compliance with any of these requirements under the EPC.

The board further held that a patent claim must be construed in an objective manner (see T 518/00, referring to the description and the drawings as an aid to interpretation). This prohibited adopting a certain claim interpretation – be it narrow or broad – only because it was, under a certain ground of opposition (or, for that matter, under a certain ground for revocation or in infringement proceedings), (more) detrimental or beneficial to one of the parties.

Abstract

In T 939/22 claim 1 of the main request was directed to "(a( vaccine comprising a recombinant nonpathogenic Marek's Disease Virus (rMDVnp) comprising a first nucleic acid (…) and wherein the rMDVnp is a recombinant herpesvirus of turkeys (rHVT)." The construction of rMDVnp was relevant for assessing novelty over D8.

The definition of rMDVnp in the description (page 7, lines 19 to 20 of the patent in suit) stated that the term rMDVnp referred to a rMDVnp that included heterologous nucleotide sequences (i.e. sequences from pathogens other than MDV). In other words, the definition in the description equated the term rMDVnp to a specific recombinant vector with inserts of nucleotide sequences encoding proteins from other pathogens. According to the board, this definition could not change the common understanding of the terms of art rMDVnp and rHVT as used in claim 1 nor was this definition consistent with how a skilled person would understand the claim. Indeed, the skilled person would understand the terms rMDVnp and rHVT as used in claim 1 to refer to the genome of a viral vector stemming from a non-pathogenic strain of an MDV serotype. No further limitations were implied by the terms rMDVnp and rHVT. The skilled person would not understand the term rHVT to exclude viral vectors in which a specific region of the genome of HVT (which is MDV serotype 3, i.e. MDV3) has been replaced by the corresponding region of a different MDV serotype, as is the case for novel avian herpesvirus (NAHV). Of course, claim 1 further required that nucleotide sequences of at least two specified pathogens other than MDV, i.e. Newcastle disease virus (NDV) and infectious laryngotracheitis virus (ILTV), be inserted into the rMDVnp/rHVT vector. Hence, the claim was directed to a construct formed by the rMDVnp/rHVT vector and inserts of nucleotide sequences from other pathogens.

The board held that the exclusion of viral constructs comprising nucleotide sequences from different MDV serotypes from the term MDVnp (page 7, lines 14 to 17 of the patent in suit) was in line with how the skilled person would understand the term MDVnp, as it did not include recombinant viral constructs but referred only to the naturally occurring viruses. Claim 1, however, was specifically directed to a vaccine comprising a recombinant non-pathogenic MDV (rMDVnp), specifically rHVT. Even if the definition of MDVnp in the description were intended to include rMDVnp in a way that excluded chimeric viruses, this could not change the skilled person's understanding of the terms rMDVnp and rHVT.

In the board's view, excluding chimeric viruses from the claimed subject-matter appeared contradictory for the following reasons. The term chimeric virus, as understood by the skilled person, related to a specific type of recombinant virus that contains genetic material from different viruses within a single viral genome construct. This typically implied that the resulting viral construct exhibits characteristics derived from each of the parental viruses. Accordingly, inserting nucleotide sequences of NDV and ILTV into the rHVT vector as claimed resulted in a chimeric virus. Therefore, chimeric viruses could not be excluded from the subject-matter of claim 1, let alone a (recombinant) NAHV that included nucleotide sequences from NDV and ILTV.

The board also noted that, due to the comprising language, claim 1 did not exclude that the rMDVnp could be engineered to comprise additional nucleic acid inserts encoding antigens of pathogens other than NDV and ILTV.

It was clear from the wording and structure of claims 3, 4, 9 and 11 that the inventors of D8 had envisaged both (i) a multivalent vaccine that was a mixture of different NAHV constructs, each encoding a separate foreign gene (claim 19), and (ii) a multivalent vaccine based on a single NAHV construct encoding a plurality of foreign genes (claim 11, to which vaccine claim 18 refers). A multivalent vaccine encoding more than one heterologous antigen was furthermore addressed in several passages of the description. D8 provided detailed instructions on how to prepare the recombinant chimeric virus and clear protocols on how to test them for their suitability as vaccines. Thus, sufficient information was provided to enable the skilled person to produce and test a composition suitable as a multivalent vaccine as defined in claim 18 of D8.

In addition, it was credible that a recombinant MDV comprising more than one insert from two different heterologous viruses in the non-essential US2 site, encoding thus one additional foreign antigen to those tested in Examples 1 to 3 of D8, could be prepared and would provide protection by preventing or reducing the severity of a disease caused by at least one of the viruses whose antigens were encoded by the recombinant MDV construct.