T 1709/20 11-07-2023

Main request (claims as granted)

1. Added-matter

1.1 Granted claim 9 pertains to a polyethylene composition defined by its preparation process. That process involves the preparation of a base resin having, among other features, "a density of more than 951 kg/m**(3) and equal to or less than 957 kg/m**(3), determined according to ISO 1183-1:2004," and "a content of units derived from 1-hexene of 0.45 to 0.95 wt.-%". The respondent argued that granted claim 9 found a basis in claim 10 as originally filed and the passage on page 8, lines 7-11 of the description.

1.2 Claim 10 as originally filed essentially corresponds to granted claim 9 without the limitation of the comonomer to units derived from 1-hexene in an amount of 0.45 to 0.95 wt.-%.

1.3 Page 8, item "g. C6 (content)" of the application as filed cited as a basis for the content in 1-hexene in the base resin discloses that "The base resin according to the present invention preferably has a content of units derived from 1-hexene of 0.45 to 0.95 wt.-%". That definition of the comonomer is part of a broader passage starting on page 6 which defines the parameters of the base resin and includes as the first parameter the information that "The base resin according to the present invention has a density of more than 952.0 kg/m**(3) and equal to or less than 957.0 kg/m**(3), preferably of more than 952.2 kg/m**(3) and equal to or less than 956.0 kg/m**(3), more preferably of more than 952.5 kg/m**(3) and equal to or less than 955.0 kg/m**(3) and most preferably of more than 953.0 kg/m**(3) and equal to or less than 954.0 kg/m**(3) determined according to ISO 1183-1 :2004." (emphasis added, item "a. Density (base resin)"). The density range in claim 9 as granted (more than 951 kg/m**(3) and equal to or less than 957 kg/m**(3)) is, however, not present in that general part of the description.

1.4 The Board does not find in the application as filed a basis for the combination of the range of 1-hexene content as defined on page 8 of the original description with the range of density disclosed in claim 10 as originally filed. This conclusion is reached by applying "gold standard" (G 2/10, OJ 2012, 376) for assessing compliance with Article 123(2) EPC which is the following: any amendment to the parts of a European patent application or of a European patent relating to the disclosure (the description, claims and drawings) is subject to the mandatory prohibition on extension laid down in Article 123(2) EPC and can therefore, irrespective of the context of the amendment made, only be made within the limits of what a skilled person would derive directly and unambiguously, using common general knowledge, and seen objectively and relative to the date of filing, from the whole of these documents as filed (Case Law of the Boards of Appeal, 10th Edition 2022, II.E.1.1).

1.5 It is apparent that the ranges of density and 1-hexene content defined in items "a. Density (base resin)" and "g. C6 (content)" on pages 6 and 8 of the original description can be read in combination because they refer the base resin "of the present invention" that is disclosed in the same part of the application as filed. Thus the description as originally filed provides a basis for a combination of 1-hexene content of 0.45 to 0.95 wt.-% and a density of more than 952.0 kg/m**(3) and equal to or less than 957.0 kg/m**(3). There is, however, no direct and unambiguous disclosure of the broader density range of more than 951.0 kg/m**(3) and equal to or less than 957.0 kg/m**(3) in the description as filed. Even the passage bridging pages 3 and 4 of the description which discloses a polyethylene composition obtainable by a multistage process analogous to that of claim 10 only defines the density of the base resin in the range of more than 952.0 kg/m**(3) and equal to or less than 957.0 kg/m**(3).

1.6 The Board therefore concludes that granted claim 9 does not find a basis in the application as filed. The ground for opposition under Article 100(c) EPC thus prejudices the maintenance of the patent in suit as granted.

2. Admittance of auxiliary requests A and 1A-4A

2.1 Auxiliary requests A and 1A-4A were submitted by the respondent with their letter of 30 May 2023. Auxiliary request A corresponds to the main request from which independent claim 9 was deleted and the subsequent claims renumbered and their back references adapted accordingly. Auxiliary requests 1A-4A correspond to the first to fourth auxiliary requests that were filed with the statement of grounds of appeal for which the claim corresponding to granted claim 9 (claim 9 in the first auxiliary request and claim 8 in the second to fourth auxiliary requests) was deleted.

2.2 Auxiliary requests A and 1A-4A are amendments to the respondent's case that were submitted in appeal after issuance of a summons to oral proceedings and of the Board's communication containing a preliminary opinion on the present case. The admittance of these amendments into the proceedings is subject to the provisions of Article 13(2) RPBA 2020, which foresees that amendments made after notification of the summons shall, in principle, not be taken into account unless there are exceptional circumstances, which have been justified with cogent reasons by the party concerned.

2.3 Auxiliary requests A and 1A-4A were provided in reaction to the ground for opposition under Article 100(c) EPC against granted claim 9 that was part of the appeal proceedings. There is no doubt that the amendment made in auxiliary requests A and 1A-4A (the deletion of the claim corresponding to granted claim 9) resolves the issue raised under Article 100(c) EPC without raising any new one. It is also not disputed that these requests do not alter the factual or legal framework of the proceedings and that their analysis does not involve a need to re-weigh in any way the subject of the proceedings. They are, therefore, not detrimental to the procedural economy or the legitimate interests of the other parties. As the purpose of the rules of procedure is not, in itself, the refusal to consider late requests, but rather the defence of the parties' rights to a fair hearing within a reasonable time (T 0732/21, point 14 of the Reasons), the Board fully endorsing the approach in T 2920/18 (points 3.10 to 3.15 of the Reasons) and T 2295/19 (points 3.4.9 to 3.4.14 of the Reasons) acknowledges the presence of "exceptional circumstances" within the meaning of Article 13(2) RPBA 2020 which justify the admittance of auxiliary requests A and 1A-4A into the appeal proceedings.

2.4 The Board therefore finds it appropriate to exercise its discretion according to Article 13(2) RPBA 2020 by admitting auxiliary requests A and 1A-4A filed with letter of 30 May 2023 into the proceedings.

3. Admittance of D15-D20 and of the objection of lack of novelty based on example 1 of D6

3.1 D15 is an academic publication concerning polyethylene resins for pipe applications cited in the discussion of inventive step starting from D6 as the closest prior art to provide evidence on the factors influencing slow crack propagation, in particular its comonomer content (section 5.4 of the statement of grounds of appeal of appellant I).

3.2 D16 is a patent document mentioned in D6 and in the patent in suit. D16 is cited in the discussion on inventive step to show that the same catalysts could be used in the production of polyethylene compositions cited in D6 and in the patent in suit (pages 6 and 7 of the statement of grounds of appeal of appellant II).

3.3 Both D15 and D16 were filed with the statements of grounds of appeal in reaction to points made in the decision of the opposition division (discussion of the slow crack propagation in the last paragraph of page 16 and the role of the catalyst in the second paragraph of page 17) and are cited to address specific arguments that had not been explicitly discussed in the written phase of the opposition procedure. They can therefore be considered as a legitimate reaction to the decision of the opposition division.

3.4 D17 and D18 are documents submitted by the respondent with the rejoinder to the statements of grounds of appeal of the appellants in direct reaction to the discussion of D15 and D16 by the appellants. They can therefore be considered as a legitimate reaction to the new submissions of the appellants.

3.5 In view of this, the Board finds it appropriate to exercise its discretion under Article 12(4) RPBA 2020 by admitting D15 to D18 into the proceedings.

3.6 D19 is a notice of opposition filed by the respondent on 26 October 2022 against European patent No. 3 794 071. D20 is an affidavit of Mr. Albrecht referred to as D13 in D19 and discussed in section 40 on page 18 of that document. Both D19 and D20 were cited in support of novelty objections based on examples 1 and 3 of D6 against granted claim 1.

3.7 D19 and D20 were filed with letter of appellant II of 18 January 2023 and with letter of appellant I of 3 July 2023, respectively. On this basis, they constitute an amendment to the appellants' case filed after the summons to oral proceedings. The conditions of Article 13(2) RPBA 2020 therefore apply (see point 2.2, above).

3.8 D19 was filed by appellant II within a reasonably short time after it became available to the public on 26 October 2022. D20 was filed by appellant I at a later point in time only to confirm the information that was already made available with the filing of D19. In view of these circumstances, both D19 and D20 can be seen as having been filed in appeal shortly after they became available to the appellants.

3.9 D19 is meant to show the amount of 1-hexene in the base resin disclosed in example 1 of D6. That is also held to be relevant for the novelty objection over example 3 in D6. D20 is the source of the data reported and discussed in D19. D19 and D20 are prima facie particularly relevant to the question of novelty as they contain data released by the respondent about a base resin of D6 (D6 is a patent application of the respondent).

3.10 The novelty objection based on D6 was firstly raised by appellant II with their notice of opposition (D6 was referred to as D1 therein). The objection was discussed in the written phase of the opposition proceedings and was also addressed by the opposition division at the oral proceedings. The 1-hexene content of the base resin in the compositions of D6 was the reason why the opposition division concluded that granted claim 1 was novel over that document (section 4.2.2). Therefore, the novelty objection over D6 is not new to the opposition proceedings and D19 and D20 are documents provided in support of a central point of the novelty objection already discussed in the decision under appeal.

3.11 The Board finds that the filing of D19 and D20 shortly after they were made available, the prima facie relevance of these documents to the central point of the question of novelty already raised in opposition, and the fact that they originate form the respondent, are exceptional circumstances that justify the admittance of D19 and D20 into the appeal proceedings. Documents D19 and D20 are therefore taken into account under Article 13(2) RPBA 2020.

3.12 The respondent also contested the admittance of the novelty objection over D6 based on its example 1. The objection of lack of novelty over D6 was indeed originally raised in view of example 3 (notice of opposition of opponent 2, pages 1-3 and impugned decision, page 10) and the objection based on example 1 was firstly raised in the letter of appellant I dated 3 July 2023.

3.13 The objection of lack of novelty raised in view of example 1 of D6 in appeal is, however, essentially the same as the objection raised from example 3, the critical question being whether the amount in 1-hexene in the base resin disclosed in example 1 or 3 of D6 is according to granted claim 1. Since D19 and D20 disclose the amount of 1-hexene of the base resin of example 1 of D6 only (0.6 wt.-% on page 19 of D19 or on line 9 of the second page of D20), an amount that can immediately be seen as being according to granted claim 1 (0.45-0.95 wt.-%), the Board finds that the objection based on example 1, which would be central to the novelty of operative claim 1, can not be reasonably ignored while a novelty objection based on D6 was already in the proceedings and after documents D19 and D20 have been admitted. The Board therefore considers the present situation as an exceptional circumstance and admits the objection of lack of novelty in view of example 1 of D6 into the proceedings (Article 13(2) RPBA 2020).

4. Remittal

4.1 The respondent requested the remittal of the case to the opposition division in order to be able to adequately react to the new objection of lack of novelty of operative claim 1 in view of example 1 of D6, and consider any consequential and necessary amendments. The appellants objected to the remittal of the case to the opposition division.

4.2 The Board finds that the late introduction of D19 and D20 into the appeal proceedings and the consideration of example 1 of D6 for novelty puts the respondent in a new situation in which they have to consider an issue in appeal based on new evidence that necessitates a new assessment of the question of novelty and possibly inventive step of operative claim 1. Moreover, such a new assessment in the light of new evidence results in a fresh case on which a decision could not be previously taken by the opposition division. In view of this, the Board considers that special reasons under Article 11 RPBA 2020 are present and finds it appropriate to remit the case to the opposition division for further prosecution (Article 111(1) EPC).