T 0224/12 02-02-2016

Reasons for the Decision

1. Admissibility of the appeal

1.1 The main request of the patent proprietor before the opposition division for rejection of the opposition was not allowed.

1.2 According to the minutes of the oral proceedings before the opposition division (section 5) when novelty of the main request was discussed the patentee did not provide any arguments. The decision records in section 4.2 that the patentee did not contradict the novelty objections of the opponent against the main request.

1.3 It is the position of the opponent that, due to the absence of arguments in support of the main request at any stage, the patent proprietor was not adversely affected by the decision.

1.4 The position of the appellant/opponent is not supported by the law.

The patent proprietor's main request was refused by the meaning that the patent proprietor was adversely affected by the decision.

Thus the requirements of Art. 107 EPC are satisfied.

1.5 The appellant/opponent appears in effect to argue that since the patentee did not advance arguments in support of the main request, it was not adversely affected.

However according to R.99 EPC the admissibility of appeal is determined by the notice of appeal. No provision exists in the EPC for basing a decision regarding the admissibility of an appeal on the nature or extent of the arguments advanced in support of a request during the first instance proceedings.

A possible sanction for presenting arguments which should have been presented before the first instance, but which were only submitted on appeal is their exclusion from the appeal proceedings in accordance with Art. 12(4) RPBA. This however has no influence on the admissibility of the appeal.

1.6 The opponent has further argued that, since the patent proprietor was no longer pursuing the main request submitted at the time of filing the appeal i.e. the patent in the form as granted, the appeal had to be seen as now - retroactively - being inadmissible. This argument is likewise not supported by law. According to Art. 107 and 108 EPC and R. 99 EPC the admissibility of an appeal is determined in the light of the facts at the time the appeal is filed.

1.7 Since the patent proprietor was adversely affected by the decision in respect of its main request, the provisions of Art. 107 EPC are satisfied.

Consequently the objection that the appeal of the patent proprietor is inadmissible because the requirements of Art. 107 EPC are not met fails to convince.

2. Main request

2.1 Admissibility

In the statement of grounds of appeal the appellant/patent proprietor pursued as the main request the rejection of the opposition, i.e. maintenance of the patent in the form as granted.

With the second letter of the appeal procedure, in response to the statement of grounds of appeal of the opponent, an amended - restricted - main request corresponding to the claims in the form as upheld by the opposition division was submitted (see section VI, above).

This request was the subject of concerns in the communication of the Board, in particular with respect to the allowability of the amendments having regard to to the presence in the claim of features taken from claims of different categories.

Compared to claim 1 of the auxiliary request underlying the contested decision, the amendments undertaken according to the main request as filed with the letter of 1 December 2015, which merely involved removal of the feature relating to the nature of the catalyst used to obtain the polymer were explicitly stated to be in order to address the above objections of the Board. The dependent claims were - apart from the deletion of claim 2 - identical to the dependent claims of the request underlying the decision under appeal.

The opponent had raised an objection specifically to the definition of the catalyst in claim 1. The patent proprietor had taken position thereon, defending the allowability thereof. However it was only after receipt of the communication, in which the Board set out its preliminary view, that the patent proprietor made the necessary amendments to overcome the objections raised by the opponent.

Although these amendments could have been made at an earlier stage of the proceedings, they are not complex, consisting in the deletion of a feature which, as noted, by the Board in its communication, was not considered to impose any restriction on the product claimed. Therefore that amendment did not result in a change of the matters to be discussed, in particular with respect to the issues of novelty and inventive step.

The appellant/opponent did not argue, let alone show, that the amendment was of such a nature or complexity that it could not be dealt with in the time remaining between the amended request being filed and the oral proceedings.

Consequently, under the present circumstances there is no reason not to admit the new main request to the proceedings.

The main request is admissible.

2.2 Art. 123(2) and (3) EPC

Claim 1 of the main request is directed to propylene random copolymers wherein the comonomer is ethylene in an amount of 6 wt.-% or lower and has a TREF elution interval of 50°C or more.

These features are disclosed in claim 18 as originally filed, which is dependent on any of claims 13-17 (see recitation of claims in section II, above). Of these, claim 16 specifies that the copolymer is prepared by copolymerisation of propylene with a comonomer, inter alia ethylene and that the copolymer has a TREF elution interval of 50°C or more. Thereby the feature relating to the TREF elution interval in combination with the comonomer being ethylene in an amount of 6 wt.-% or lower is disclosed by claim 18 in its dependency on claim 16.

Operative claim 1 further specifies that the random copolymer has a xylene solubles content of from 5 to 15 wt.%.

This feature is disclosed in originally filed claim 24 as the "more preferred" embodiment, which claim was dependent on any of claims 13-23, thus also claim 18.

Consequently the subject-matter of operative claim 1 corresponds to the subject-matter of one embodiment of originally filed claim 24 in its dependence on claim 18.

The further claims correspond to originally filed claims 17 (dependent on any of claims 13-16 and on which claim 18 was dependent), 20, 22, 24 and 25 of the application as originally filed.

With respect to operative claim 2, the melting point of 135°C or higher is disclosed at page 9, 4th complete paragraph of the application as originally filed as being preferred in the case of the embodiment in which the TREF interval is 50°C or more, which feature is present in operative claim 1.

Operative claim 1 furthermore corresponds to the copolymers demonstrated in the examples, confirming that this subject-matter was part of the original disclosure.

The requirements of Art. 123(2) EPC are thus satisfied.

The opponent did not object that the amendments to the patent as granted extended the scope of protection and the Board has no reason to take a different view of this matter. Therefore the main request is also considered to be in accordance with the requirements of Art. 123(3) EPC.

2.3 Art. 83 EPC - admissibility of the ground

The objections raised by the appellant/opponent relate to the certainty or precision of the result of the TREF analysis.

This aspect however affects the question of the feasibility of ascertaining whether a given product falls within the scope of the claims, which is a matter governed by the provisions of Art. 84 EPC.

It has neither been argued nor demonstrated that it would not be possible to prepare the propylene random copolymer as specified according to claim 1 of the main request, or the film of claim 6 thereof.

Consistently with the above analysis, the decision of the opposition division not to admit the ground of opposition pursuant to Art. 100(b)/83 EPC, although somewhat brief in its reasoning, was based on the finding that the objections raised related to Art. 84 EPC and not to Art. 83 EPC. Consequently the decision of the opposition division relating to the admissibility of the ground pursuant to Art. 100(b) EPC to the proceedings was taken on the basis of a correct appraisal of the underlying facts and according to the correct principles.

As the objections raised by the appellant/opponent were not considered to relate to Art. 100(b) EPC the question of prima facie relevance of the ground pursuant to Art. 83 EPC, invoked by the appellant/opponent in its submissions on appeal does not arise.

The ground of opposition pursuant to Art. 100(b)/83 EPC is not admitted to the proceedings.

2.4 Art. 54 EPC

2.4.1 Meaning of the feature "TREF elution interval" and relation thereto of the xylene soluble fraction

The appellant/opponent disputed that the TREF interval was unambiguous due to uncertainty as to how the xylene soluble fraction was to be taken into account. According to the opponent this fraction would elute first and it would be impossible to distinguish this from the elution of the crystalline fractions which had deposited on the column, meaning that the TREF elution interval could not be reliably determined.

However as is apparent from e.g. D2, page 868 the purpose and background to TREF analysis is to progressively elute from a column, as the temperature increases, crystalline fractions which have been precipitated onto the column by gradual cooling from solution. Fractions which were soluble in the solvent used, and which consequently did not precipitate would thus not be present in precipitated form on the column and hence would not be eluted. This is confirmed by D13, page 1641 RH column which states that polymer fractions which remain in solution are removed as the first fraction, and are not taken into account in the TREF analysis.

Consequently the very definition of TREF, i.e. Temperature Rising Elution Fractionation (emphasis of the Board) excludes that soluble fractions are taken into account since these, due to the fact that they are not deposited on the column, can not be eluted. The ambiguity postulated by the opponent with respect to TREF therefore does not exist.

2.4.2 Novelty over D3

Example 1 of D3 relates to a process whereby a copolymer of propylene and 3.6 wt.-% ethylene is prepared in a two stage reactor cascade, both monomers being present in each stage. A Ziegler-Natta catalyst is employed. The ethylene content is thus within the range of 6 wt.-% or lower required by operative claim 1.

The xylene solubles content of the polymer is 7.9 wt.-% and thus likewise within the claimed range.

A TREF interval for the polymer is not reported.

The appellant/opponent did not advance any evidence relating specifically to the process of D3.

Instead, the appellant/opponent argued that the use of a Ziegler-Natta catalyst to prepare polymers of propylene and ethylene would inevitably result in a TREF interval as required by the operative claim, i.e. such an elution interval was "inherent" to propylene/ethylene copolymers produced by processes employing Ziegler-Natta catalysts.

In support of this argument the opponent referred to D5 and D6.

It is correct that both of these documents show that, for the polymers prepared with Ziegler-Natta catalysts, elution intervals of greater than 50°c are obtained.

However, in contrast to D5 and D6, the evidence of the examples of the patent in suit itself, all of which employ a Ziegler-Natta catalyst in a two stage process, is that such a catalyst does not inevitably result in a propylene/ethylene copolymer having an ethylene content of less than 6 wt.-% and an elution interval of greater than 50°C.

Example 1 of the patent employs a gas phase reactor followed by a loop reactor and results in a copolymer having 3.3 wt.-% ethylene and an elution interval of 30.2°C, whereas comparative example 2, employing two loop reactors, results in a copolymer having 3.2 wt.-% ethylene and an elution interval of 40.9°C.

Accordingly the submissions of the appellant/opponent with respect to the inevitability or inherence of the polymers of D3 having an elution interval of at least 50°C as a result of them being prepared with a Ziegler-Natta catalyst is not supported by the evidence.

Consequently there is no evidence - either direct or indirect - that the elution interval of the polymers of D3 would inevitably be within the claimed range of at least 50°C.

The subject-matter of operative claim 1 is thus distinguished from the disclosure of D3 by the specified elution interval.

2.4.3 Objection of lack of novelty over the published patent derived from the priority document of the patent in suit.

This objection was raised for the first time in the entire proceedings in the letter of 15 December 2015, i.e. after issue of the summons to the oral proceedings.

According to the appellant/opponent the "trigger" for the new argument was the position taken by the Board with respect to Art. 123(2) EPC in its communication.

This however cannot be accepted since the Board's position was based solely on the objections already raised by the opponent. Thus there is no proper justification for raising that objection at this stage of the proceedings.

Furthermore, the arguments submitted by the opponent are based on EP-B-1 270 628 and thus on the patent that was granted on the application from which priority is claimed. Accordingly the argumentation of the opponent is as such not appropriate to assess the disclosure of the document from which priority is claimed. The specific ranges of ethylene content and xylene solubles content as now claimed do not appear to be disclosed in the published priority document, but appear to broadly overlap with the ranges disclosed therein. Also the disclosure of the priority document which is cited as novelty destroying - examples 2 and 4 - is also present in the application as originally filed and in the granted patent.

Furthermore, assuming that the disclosure of EP-B-1 270 628 would correspond to that of the priority document, the issues raised by the opponent relate to the complex issue of partial priority currently pending before the Enlarged Board of Appeal as referral G 1/15. Accordingly, the amendment to the opponent's case, i.e. the objection that the claimed subject-matter would lack novelty over its own priority, which objection was sought to be made after oral proceedings had been convened, cannot be admitted to the proceedings as this objection raises issues which the Board could not reasonably be expected to deal with without adjournment of the proceedings, contrary to the requirements of Art. 13(3) RPBA.

2.4.4 No other objections pursuant to Art. 54 EPC being pursued, the Board concludes that the requirements of Art. 54 EPC are satisfied.

2.5 Art. 56 EPC

2.5.1 Closest prior art

The patent in suit relates to propylene random copolymers.

According to the patent in suit it is known that important properties of propylene random copolymers such as film transparency or xylene insolubles content are decisively influenced by the comonomer distribution. Conventional processes usually only allow for limited fine-tuning of comonomer distribution whereby the comonomers are concentrated in short polymer chains which negatively affects the properties of the copolymers and increases the content of - undesirable - xylene solubles (paragraphs [0005]-[0007]). According to paragraphs [0008] and [0009] of the patent in suit the problem addressed is to provide propylene random copolymers with properties which can be fine-tuned by tailoring the comonomer distribution and to provide propylene random copolymers with a reduced content of xylene solubles.

The polymers are intended for uses such as blow moulding, injection moulding, fibres and pipes (paragraph [0014]).

D3, which document according to the decision and the submissions of the opponent represents the closest prior art relates according to claim 1 to high molecular weight polypropylene/ethylene copolymers with an ethylene content of 1 to 10 wt.-% and a broad molecular weight distribution (6-20). The polymer is prepared by a Ziegler-Natta process. The polymer of example 1 has a molecular weight distribution of 9.0. The ethylene content is 3.6 wt.-% and the xylene solubles content is 7.9 wt.-%, both of which lie within the scope of operative claim 1.

The problem addressed by D3 is to provide moulding compositions which can be processed on conventional machinery to produce pipes having toughness and rigidity together with durability (page 2 lines 21-24).

The patent proprietor disputed that D3 represented the closest prior art, but did not propose an alternative.

Under these circumstances, considering the structural similarity of the products claimed and their common use, the Board sees no reason to depart from the position of the decision under appeal with respect to the identity of the closest prior art.

2.5.2 Problem to be solved

Contrary to the submissions of the appellant/patent proprietor, the discrepancies between the examples of the patent in suit are such that it is not possible to ascertain whether any technical effect is associated specifically with the distinguishing feature over D3, i.e. the TREF elution interval.

Under these circumstances the only technical problem that be formulated with respect to D3 is to provide further polypropylene random copolymers in line with the submissions of the appellant/opponent.

2.5.3 Solution

This problem was solved by providing propylene random copolymers of present claim 1 characterised, inter alia by a TREF elution interval or 50°C or more.

2.5.4 Obviousness

As noted above, D3 is silent with respect the TREF elution temperature range. Nor does D3 contain any discussion relating to those properties of the copolymer which are quantified or measured by the TREF parameter.

As explained in the patent (paragraph [0043]) the TREF elution interval reflects the internal structure of the polymer, i.e. the distribution of crystalline domains, which in turn is a consequence of the isotacticity or comonomer distribution within the copolymer. This statement is consistent with the teachings inter alia of D2, D5 and D6.

Consequently the TREF elution interval is not an arbitrary parameter but reflects a (molecular) structural property of the polymer which is directly linked to the technical problem as set out in the patent in suit, namely the tailoring of the comonomer distribution within the polymer.

D3 is silent with respect to the comonomer distribution within the copolymer and does not contain any discussion of the consequences of modifying this distribution, nor of how this distribution may be controlled.

Furthermore, D3 does not teach how to control the comonomer distribution with the copolymer, while keeping the xylene soluble content within the range now claimed.

Consequently D3 itself does not render the subject-matter claimed obvious.

It has also not been argued that any document would, in combination with D3, render the subject-matter claimed obvious.

2.5.5 The subject-matter of the main request thus meets the requirements of Art. 56 EPC.