T 0058/19 - Ideally the CPA should

Key points

• This opposition appeal case demonstrates how the choice of the CPA can be important.
• As a preliminary procedural point, the decision also illustrates that the appellant can use a rejoinder to submit evidence in reply to assertions that the respondent makes in his statement of reply.
• "The admittance of D12, D12a and D13 which were filed by the appellant after the statement of grounds of appeal, but before notification of the summons to oral proceedings, is subject to the stipulations of Article 13(1) RP[]showing the publication date of D12 and D13 were submitted to refute the respondent's assertions according to which [...]. On that basis and in view of the absence of any objection to their admittance by the respondent, the Board makes use of its discretion pursuant to Article 13(1) RPBA 2020 and admits D12, D12a and D13 into the proceedings."
• On to the inventive step over D1. "According to the case law [...] ideally the closest prior art should be a document that mentions the purpose or objective indicated in the patent in suit as a goal worth achieving. The aim thereof is that the assessment process should start from a situation as close as possible in reality to that encountered by the inventor, avoiding ex post facto considerations."
• "According to paragraph [0014] of the specification, the aim of the present invention was to provide VDF-TrFE copolymer materials which can efficiently undergo crosslinking under thermal or UV exposure conditions, yielding a uniformly cured material which still maintains outstanding piezoelectric, ferroelectric, pyroelectric and dielectric properties."
• "D1 merely address the use of the materials described in D1 "in the areas of curable elastomers and elastoplastics, adhesion enhancement, coatings, thermosetting resins, grafting polymers and the like" (paragraph [0013]). It does not address electric properties of the materials described in D1, let alone piezoelectric, ferroelectric, pyroelectric and dielectric properties which are at the core of the invention described in the patent in suit."
• "Summing up, reading into D1 that this prior art discloses copolymers comprising VDF and TrFE repeating units or using that document as starting point for assessing inventive step when it does not relate to the aim of the present invention, i.e. crosslinking VDF-TrFE copolymer materials while maintaining their piezoelectric, ferroelectric, pyroelectric and dielectric properties, can only be the result of an inadmissible analysis of D1 made with the hindsight knowledge of the invention described in the patent in suit, as is submitted by the respondent."
• "Therefore, the appellant's objection that the subject-matter of claim 1 lacks an inventive step starting from the disclosure of D1 fails to convince."
• The Board then finds the claim to be inventive starting from D2 and starting from D4.
• As a comment, it seems remarkable that the Board begins with "ideally the closest prior art should be a document that mentions the purpose or objective indicated in the patent in suit as a goal worth achieving", and seems to find that because D1 fail to mention the purpose, it is not a suitable starting point at all and any inventive step argument starting from it must fail. 

EPO T 0058/19

The link to the decision is provided after the jump, as well as (an extract of) the text of the decision.

https://www.epo.org/law-practice/case-law-appeals/recent/t190058eu1.html

Inventive step starting from D1

5. According to the case law (Case Law of the Boards of Appeal of the EPO, 9th Edition, 2019, I.D.3.2) ideally the closest prior art should be a document that mentions the purpose or objective indicated in the patent in suit as a goal worth achieving. The aim thereof is that the assessment process should start from a situation as close as possible in reality to that encountered by the inventor, avoiding ex post facto considerations.

According to paragraph [0014] of the specification, the aim of the present invention was to provide VDF-TrFE copolymer materials which can efficiently undergo crosslinking under thermal or UV exposure conditions, yielding a uniformly cured material which still maintains outstanding piezoelectric, ferroelectric, pyroelectric and dielectric properties.

6. The appellant argues that D1 discloses semi-crystalline fluoropolymers (reference being made to paragraph [0024]) which comprise recurring units of monomers including VDF (i.e. VF2 in D1), TFE and/or TrFE, wherein VDF and TFE monomers are listed amongst preferred monomers in paragraph [0022] of said document. The polymers are also indicated in paragraph [0021] to comprise from 0.02 to 10 mol.% of units of fluoroalkanesulfonyl azide compounds. Concerning the achievement of ferroelectric properties, those are according to the appellant inherent in the combined use of VDF and TrFE, reference being made to D3 and D4.

6.1 Paragraph [0022] of D1 defines a list of monomers suitable for forming copolymers with the fluoroalkane-sulfonyl azide compounds (I) and (II) defined in paragraphs [0014] (or claim 1) and [0016] (or claim 3), respectively. This list of comonomers in paragraph [0022], however, does not provide a direct and unambiguous disclosure for a copolymer comprising in addition to a compound of formula (I) or (II) both monomeric units derived from VDF and TrFE.

6.2 Moreover, the indication by the appellant that the fluoropolymers envisaged in D1 are semi-crystalline merely represents one option disclosed in paragraph [0024] of D1, as this passage also refers to amorphous copolymers. Accordingly, the mere disclosure in D1 of VDF, TFE and/or TrFE is also not necessarily to be read in the context of semi-crystalline copolymers. Furthermore, having regard to paragraph [0032], the copolymers prepared in the examples of D1 are either partially crystalline, in which case a melting temperature Tm was measured, or non-crystalline in which case a Tg value was measured. In view of the Tm and Tg measurements described in the examples of D1, the sole copolymers exemplified in D1 which are disclosed to be partially crystalline are those described with examples 8 and 11, which both comprise TFE, but no VDF or TrFE units. The other copolymers exemplified in D1 comprise either TFE or VDF. They are all amorphous having regard to the indication of a Tg value.

6.3 Apart from an implicit disclosure of ferroelectric properties, based on the alleged disclosure of copolymers comprising VDF and TrFE repeating units, no indication for such properties in D1 was put forward by the appellant. D1 merely address the use of the materials described in D1 "in the areas of curable elastomers and elastoplastics, adhesion enhancement, coatings, thermosetting resins, grafting polymers and the like" (paragraph [0013]). It does not address electric properties of the materials described in D1, let alone piezoelectric, ferroelectric, pyroelectric and dielectric properties which are at the core of the invention described in the patent in suit.

6.4 Summing up, reading into D1 that this prior art discloses copolymers comprising VDF and TrFE repeating units or using that document as starting point for assessing inventive step when it does not relate to the aim of the present invention, i.e. crosslinking VDF-TrFE copolymer materials while maintaining their piezoelectric, ferroelectric, pyroelectric and dielectric properties, can only be the result of an inadmissible analysis of D1 made with the hindsight knowledge of the invention described in the patent in suit, as is submitted by the respondent.

6.5 Therefore, the appellant's objection that the subject-matter of claim 1 lacks an inventive step starting from the disclosure of D1 fails to convince.