T 2020/13 - Don't ignore the opponent in appeal

Key points

• The Board does not admit experimental report D25, filed two days before the oral proceedings.
• " The indication by the Board in section 13.2 of the communication that it might be necessary to address the relation between the structural feature of the claims (structure of the catalysts) and their ability to solve the problem allegedly solved by the claimed subject-matter [] was not an invitation to file additional experimental data. The point raised by the Board [] refers not only to the usual and necessary analysis for assessing the success of the solution proposed by the patent under examination, but also stems from the criticism exercised by the opponent that claim 1 covers a very broad range, while some of the claimed catalyst composition had not been shown to solve the technical problem underlying the patent in suit. Accordingly, the patent proprietor should not have waited until two days before the oral proceedings and more than two and an half years after the last substantive submissions of the opponent to file experimental data D25, but submit it in a timely manner to allow the opponent sufficient time to provide a response thereto. " 

Admittance of D24 and D25

3. The filing of experimental reports D24 and D25, submitted after the summons to attend oral proceedings, respectively after the subsequent Board's communication, represents an amendment to a party's case and their admission to the proceedings is subject to the Board's discretion pursuant to Articles 13(1) RPBA taking into account the additional condition of Article 13(3) RPBA. Their late submission was, according to the patent proprietor, not only due to a change of the patent proprietor and responsibility within the company making it difficult to get experimental data to address the inventive step issue, but also triggered by the new focus brought by the Board in its communication on the question whether all catalyst packages falling within the ambit of claim 1 could provide polyurethane foams and/or provide the alleged reduction of VOC and FOG values.

3.1 The theoretical possibility that D24 would be a reaction to the communication of the Board must be excluded as D24 and its accompanying submissions were filed earlier than the Board's communication. The submission of D24 with letter of 2 June 2017 concerning the use of amino-ethyl-piperazine and N,N-dimethyl-dipropylenetriamine as gelling catalysts is rather in response to the submissions of the opponent of 29 December 2014 with experimental report D23, as confirmed in section 3.1 on page 11 of the letter of the patent proprietor of 2 June 2017 (those catalysts were referred to as catalysts G and H by the opponent) Hence, the difficulties related to the assignment of the present patent to another proprietor also cannot justify the filing of D24, since said assignment took place on 3 January 2017 as indicated with letter of the new patent proprietor of 23 March 2017, i.e. 2 years after the submission of D23 which let ample time for the former proprietor to submit an appropriate response thereto.

3.2 Therefore, the Board does not find any justification for the late filing of D24 and taking into account the relevant criteria, in particular the principle of procedural economy, finds it appropriate to exercise its discretion by not admitting document D24 into the proceedings (Article 13(1) RPBA).

3.3 Concerning D25, this experimental report provides additional data concerning the use of N,N,N'-trimethyl-N'-3-aminopropylbis(aminoethyl) ether as blowing catalyst in combination with the 3 gelling agents used in the examples of the patent in suit, but varying the catalyst concentration or the isocyanate index, and the use of N,N,N'-trimethyl-N'-2-hydroxyethylbis- (aminoethyl) ether together with dimethylaminopropyl-amine. Its purpose is to demonstrate that the combinations of blowing and gelling catalysts within the definition of the present claims result in reduced emissions expressed in terms of VOC and FOG values. The issue whether the catalyst packages falling within the ambit of claim 1 could provide polyurethane foams and/or provide the alleged reduction of VOC and FOG values, i.e. whether the problem mentioned by the patent proprietor could be considered to be successfully solved across the whole area claimed, is not only standard practice when assessing inventive step, but also as indicated in section 13.2 of the Board's communication a point raised by the parties in appeal proceedings (see letter of the opponent of 29 December 2014, pages 5 to 8, points 11 to 19). The indication by the Board in section 13.2 of the communication that it might be necessary to address the relation between the structural feature of the claims (structure of the catalysts) and their ability to solve the problem allegedly solved by the claimed subject-matter (ability to form foams and reduce emission values) was not an invitation to file additional experimental data. 

The point raised by the Board in the above mentioned section of the communication refers not only to the usual and necessary analysis for assessing the success of the solution proposed by the patent under examination, but also stems from the criticism exercised by the opponent that claim 1 covers a very broad range, while some of the claimed catalyst composition had not been shown to solve the technical problem underlying the patent in suit. Accordingly, the patent proprietor should not have waited until two days before the oral proceedings and more than two and an half years after the last substantive submissions of the opponent to file experimental data D25, but submit it in a timely manner to allow the opponent sufficient time to provide a response thereto. 

Also, the difficulties related to the assignment of the present patent to a new proprietor and the change of responsibility within the company of the patent proprietor invoked cannot justify the late filing of D25, because the two years between the last substantive submissions of the opponent and the assignment of the patent in suit to the new proprietor were amply sufficient to provide additional experimental evidence if deemed necessary. While the Board does not find any justification for the late filing of D25, its admittance would also put the opposing party in the position of not being able to properly reply to it without adjournment of the oral proceedings.

3.4 On this basis, the Board does not admit document D25 into the proceedings (Article 13(1) and 13(3) RPBA).

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5.5.3 Accordingly, there is no reason for the Board to consider that it is has been made empirically credible with the experimental tests submitted by the parties that the selection of blowing and gelling catalysts in accordance with claim 1 is associated with the achievement of any particular low emission values associated with back reactions relating to the tertiary amine catalysts incorporated within the foam structure.

5.5.4 Although a technical explanation as to why an alleged effect is considered to occur over the whole scope claimed is not a prerequisite for acknowledging the presence of an inventive step, such explanation can nevertheless be taken into account to render it credible in the absence of persuasive experimental evidence that such effect is indeed obtained over the whole scope claimed. The explanation by the patent proprietor that the catalyst was stably bonded within the polymeric structure also upon heating, reducing thereby the amount of back reactions and emissions of products associated with such back reactions, has not been made in relation to the structure of the gelling and blowing catalysts defined in claim 1. Apart from the presence of a tertiary amine necessary for the catalytic activity and the presence of a reactive group which will react with isocyanate moieties, which also are common structural features to all catalysts tested irrespective of whether they are in accordance with the invention or comparative catalysts, no structural feature common to the catalysts of the present invention was indicated by the patent proprietor, let alone any explanation as to why such common structural feature is believed to lead to less back reactions and emissions associated therewith. Accordingly, the patent proprietor did not demonstrate why despite the absence of adequate experimental evidence it was still credible that the alleged reduction of emissions took place having regard to the structural features of the gelling and blowing catalysts defined in claim 1.

5.6 Consequently, it follows from the above analysis that the patent proprietor has not presented any corroborating evidence or explanations rendering it credible that the purported technical effect of producing polyurethane foams having reduced emissions in comparison to those obtained in the closest prior art is successfully achieved over the whole scope of claim 1. Accordingly, any such advantage of the claimed catalyst compositions over the closest prior art cannot be taken into account for the purpose of assessing inventive step. Thus, in view of the teaching of D8, the problem underlying the claimed invention must be reformulated and can only be seen as the provision of catalytic compositions exhibiting reduced emissions in comparison to non-reactive amine catalysts, i.e. the same result as that described in D8.

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6.4 Accordingly, faced with the problem identified in above section 5.6 and following the hint given in D8 to search for gelling catalysts which comprise a tertiary amine group and contain a reactive amino group as to incorporate that catalyst into the polyurethane structure, it was obvious for the skilled person to try N,N-dimethyl-1,3-propanediamine described in D10 or the catalysts of D14 identified in above paragraph 6.3, in particular N,N-bis(3-dimethylaminopropyl)-1,3-propanediamine, which fulfill the structural and functional requirements suggested in D8 and to use them in combination with the blowing catalyst JEFFCAT® ZF-10 also recommended in D8, thereby arriving in an obvious manner at catalytic compositions falling within the ambit of claim 1 of the first auxiliary request.

6.5 For the following reasons, the Board is not convinced by the additional submissions of the patent proprietor in support of the presence of an inventive step:

6.5.1 The fact that the skilled person had several alternatives at his disposition in D8 when looking for the provision of a further catalytic composition exhibiting reduced emissions in comparison to non- reactive amine catalysts has no impact on the assessment of inventive step, since a mere choice from a host of possible solutions offered in that document, including also hydroxyl group containing gelling catalysts and gelling catalysts from the imidazole group, does not in itself involve inventive ingenuity (see decision T 939/92, points 2.5.2 and 2.5.3 of the reasons). The obviousness of a measure depends on the goal to be achieved and in the present case, the problem to be solved does not comprise the achievement of a particular processing window or of specific properties of the foam produced. Accordingly, indication of certain processing windows or properties of the foams obtained with the type of gelling catalysts described in D8 has contrary to the opinion of the patent proprietor no influence on the choice of the skilled person and no specific motivation is required for him to make an arbitrary choice among the catalysts suggested in that document when all of them are indicated to lead to a reduction of emissions.

6.5.2 Both D8 and D10 explain how they successfully solved the task of finding a non-fugitive gelling catalyst when a non-fugitive blowing catalyst is used. Accordingly, the indication in those documents that such task would be a complex challenge, as confirmed in D1, does not necessarily discourage the skilled person to search for further catalytic compositions leading to reduced emissions in comparison to non-reactive amine catalysts, but on the contrary guides him, as shown in the above assessment of inventive step, to follow the teaching and suggestions provided in D8 and D10 paving the way for embodiments in accordance with the invention as defined in the contested patent. In particular, the skilled person is warned in D8 that some catalysts having a low vapour pressure could form azeotropes with other compounds, especially water, and therefore could increase the amine emission. Accordingly, he would be encouraged not only to use gelling agents having the structure suggested in D8 or D10, which are reported in those documents to lead to a reduction of the amine emissions, but also those suggested in D14 which are based on the same or a similar structure as shown above.

6.6 Accordingly, the subject-matter of claim 1 of the first auxiliary request which encompasses obvious embodiments does not meet the requirements of Article 56 EPC.