T 2043/07 13-01-2010

1. The appeal is admissible.

2. Art 114(2) - EPC Admissibility of the submission of the appellant/opponent of 7 August 2008

2.1 The submission of 7 August 2008, which was the second submission of the appellant/opponent in the appeal proceedings (see section VII, above) had been filed outside the period allowed for filing an opposition (Art. 99(1) EPC) and also outside the time period permitted for filing an appeal (Art. 108 EPC). These facts are not disputed.

2.2 As reasons for the late filing it was explained that it been a "stroke of luck" finding the sample and the associated documentation since the requirement for retention of documentation was only seven years (see sections XII.(a) and XIII.(a), above). No arguments or evidence were advanced by the respondent/patent proprietor which would give the Board cause to doubt this. In view of the uncontested submissions of the appellant/opponent the Board is satisfied that at the time of filing the opposition in March 2005, i.e. almost nine years after the alleged public prior use, the relevant samples and documentation could no longer have been expected to be present in the archives either of the appellant/opponent or of any recipients of the material. Consequently no grounds have been advanced to suggest that, as a matter of course, there would have been a reliable, systematic means by which samples and documentation dating from this time period could have been retrieved at the time of preparing the opposition. Thus there are no reasons for concluding that this information had been deliberately withheld from the opposition procedure. Regarding the question of the analyses of the sample the respondent/patent proprietor commented on this both under the aspect of substantive consideration of the data (see submission of 16 April 2009, reported in section X.(c) above), and in terms of the admissibility thereof (submissions at the oral proceedings before the Board, reported in section XIII.(a), above). The Board considers this aspect belongs not to a consideration of the admissibility of the data but to the evaluation of the substantive merits of the objection, and hence consideration of this aspect will be deferred. Similarly the question of the size of the delivery, i.e. whether this was a commercial delivery also belongs under a consideration of the substantive aspects (cf submissions of the respondent/patent proprietor at the oral proceedings reported in section XIII.(a), above).

2.3 According to Art. 13(1) of the Rules of Procedure of the Boards of Appeal (in the form which entered into force on 13 December 2007) any amendment to a party's case after it has filed its grounds of appeal may be admitted and considered at the Board's discretion. In exercising this discretion inter alia the complexity of the new subject matter submitted, and the current state of the proceedings are to be considered.

2.3.1 Regarding the complexity of the new matter it is apparent that this data was submitted in order to address a deficiency in the opponent's case that had been identified by the opposition division, specifically the absence of analytical data relating to the product D-KX412CS (see section III.(c), above). Consequently, the relationship of this new data to the submissions already made and the relevant legal issues underlying the case are immediately apparent and thus in the context of the procedure at the time it was submitted this matter could not be considered to be of high complexity.

2.3.2 Regarding the second of these aspects, i.e. the state of the proceedings, it is appropriate to recall that at the time the appellant/opponent made the submission of 7 August 2008 the respondent/patent proprietor had not yet made any substantive response to the appeal but had already requested, and been granted a (first) extension of two months to the period for responding to the statement of grounds of appeal, i.e. until 9 September 2008 (letter of the respondent/patent proprietor of 8 July 2008, communication of the Board dated 21 July 2008). A further extension, until 9 October was granted by the Board in a communication of 10 September 2008 in response to a request from the respondent/patent proprietor dated 3 September 2008. In its communication allowing this request, the Board made explicit reference to the letter of the opponent of August 2008 as justification for according the extension. Accordingly the submission of the appellant/opponent of 7 August 2008 did not prima facie necessitate a modification of the position taken by the respondent/patent proprietor in its submissions to the Board since at the time of making the submission of 7 August 2008 the respondent/patent proprietor had not as yet taken position on the appeal. These considerations are not affected by the fact that, for whatever reason, this submission was not communicated to the respondent/patent proprietor until 16 December 2008.

2.3.3 Accordingly it is concluded that with regard to the provisions of the rules of procedure regarding late submissions that it would be appropriate for the Board to exercise its discretion to admit the submission of 7 August 2008 to the procedure.

2.4 Regarding the jurisprudence developed with respect to late submissions, it is recalled that according to the principles set out in section 3.4 of the reasons of T 1002/92 (OJ EPO 1995, 605), in proceedings before the boards of appeal new facts and evidence which go beyond that presented in the notice of opposition should only be admitted - exceptionally - if such new material is prima facie highly relevant in the sense that it is highly likely to prejudice maintenance of the patent in suit. Since the submission of 7 August 2008 contained evidence relating to a sale of an identified batch (lot) of D-KX412CS and also an analysis of this batch, and thus directly addressed a deficiency in the case of the opponent identified in the decision under appeal (see above), the Board has to conclude that, prima facie this data was highly relevant.

2.5 Accordingly in view both of the provisions of the Rules of Procedure of the Boards of Appeal and the relevant case law the Board concludes that it is appropriate to exercise its discretionary powers to admit the submission of 7 August 2008 to the procedure (Art. 114(2) EPC).

3. Art 54 EPC - Novelty

Lack of novelty has been alleged based on public prior use of the product D-KX412CS (see sections II, III.(c), V.(a) VII, IX.(c), XII.(a), XII.(b) and XIII.(b), above).

3.1 A number of pieces of evidence have been submitted in support of this objection:

- together with the notice of opposition a copy of a writ served on the present appellant/opponent by the respondent/patent proprietor relating to infringement of a patent by D-KX412CS (D5);

- together with the letter dated 6 July 2007 the opponent submitted as part of D16 two invoices relating to transactions involving 4000Kg and 3200Kg of D-KX412CS, the invoices bearing dates of 17 July 1997 and 11 November 1997;

- in the statement of grounds of appeal it was explained that the lot number indicated on the invoices forming D16 (670626) indicated that the product in question had been made on 26 June 1997;

- finally with the letter dated 7 August 2008 (see section VII, above) the appellant/opponent provided an invoice relating to a transaction involving 2140 Kg of D-KX412CS. The invoice recorded the shipping date as 8 May 1996 and the date of receipt as 9 May 1996. The invoice bore two lot numbers, 660314 and 651223. It was explained that the lot 660314 had been produced in 1996, employing an extruder with a die diameter of 2.5mm. It was stated that some samples of the lot 660314 had been found and that the joint venture partner KJE had been able to retrieve the invoice. The properties of KX412CS from lot number 660314 were reported, all of which fell within the scope of the corresponding features of operative claim 1. Further an affidavit ("Imachi") was provided which stated inter alia that particle size distribution was not a sales or product specification and that the particle size distribution of KX412CS would likely differ slightly from production lot to production lot.

3.2 Regarding the evidence provided by the writ D5 it is apparent from pages 2 and 3 thereof that the claims of the patent of which infringement was being alleged did not specify the bulk density, the particle size distribution or the total pore volume of the polymer, i.e. features (e)-(g) of operative claim 1. Nor is there any further statement in D5 relating to these properties. Accordingly D5 fails to establish even the existence of an allegation that D-KX412CS exhibited all the features of operative claim 1. This conclusion is not altered by the theoretical possibility, as argued by the appellant/opponent that these properties could have been determined by the skilled person (see section XIII.(b), above).

3.3 The invoices submitted as part of D16 provide only a disclosure of the product grade (D-KX412CS) and the production batch (670626). However as no details were provided of the properties of this product there is no evidence that this exhibited the properties required by operative claim 1.

3.4 The invoice submitted together with the letter of 7 August 2008 records two batch numbers. For one of these an analysis has been provided.

3.4.1 With respect to the presence of two lot numbers on the invoice, it has been submitted by the appellant/opponent and not challenged by the respondent/patent proprietor, that polymer from the different lots would be separately packaged (into 20kg sacks) and that the packages would be marked with the respective lot numbers. In the light of this uncontested statement the Board has no grounds for doubting that polymer resulting from production lot 660314 would have been delivered - as part of the consignment recorded in the invoice - in a pure, unmixed form and hence product of the specified grade identifiably derived from this production batch would have been made available and could have been analysed.

3.4.2 The Board is satisfied that the amount delivered - over 2 tonnes - constitutes an amount which could plausibly be seen as a commercial delivery rather than a sample e.g. for test purposes. In this connection the Board considers that it is immaterial precisely which proportion of the consignment was derived from the lot or batch for which analytical data had been provided. As submitted by the appellant/opponent at the oral proceedings (see section XIII.(a), above), and not contested by the respondent/patent proprietor, such a transaction would be in respect of a specified amount of a defined (commercial) grade of polymer, not of a specific production batch thereof. Accordingly the Board is satisfied that the delivery reported was of a commercial nature and that the entirety thereof was made available to the recipient on a non-restricted commercial basis.

3.4.3 However a number of questions arise regarding the determination of the properties of the product. In the letter of 7 August 2008 it is stated that some samples of KX412CS, lot number 660314 had been "found". It is however not stated where and under what circumstances these had been "found", for example to whom it had originally been delivered, or when. No information is provided about "KJE", or the nature of the joint venture. There is furthermore no information relating to the manner in which the sample had been stored in the period between manufacture (1996) and being found (2008) - a period of 12 years. Thus it is not possible to conclude that no changes to the product constitution had occurred during the period of storage or even to estimate the nature of the likely changes. Further it is not possible on the basis of this information to ascertain whether the "found" sample derived from batch 660314 corresponded in all respects, specifically particle size, to that which had been delivered according to the invoice submitted. In particular, as witnessed in the Imachi affidavit of 11 June 2008 attached to the 7 August 2008 letter, particle size was not a sales or product specification. Consequently there is no basis for assuming that the particle size of that portion of the named batch which had been "found" necessarily and inevitably corresponded to the particle size of that portion of the batch which had been delivered according to the invoice submitted. The doubts in this respect are only compounded by the absence, noted above, of any information concerning the identity of the recipient of the batch that was "found" and analysed.

3.4.4 The report of the properties of this product in the letter of 7 August 2008 is also deficient and, as established by statements made by the appellant/opponent in the submission of 14 December 2009 and made at the oral proceedings before the Board, incomplete. In particular only results are presented. There is no information in the letter of 7 August 2008 regarding by whom or when the analyses were carried out. No information is provided regarding the precise manner in which the analyses had been carried out, nor are the underlying data which gave rise to the reported values and conclusions reported. It was only in the letter of 14 December 2009 that it was disclosed that the analytical data had been obtained by Kraton Polymers in collaboration with the Delft University of Technology, and that the analyses had been carried in accordance with the methods described in the patent. However even at this point no detailed report of the analyses was provided, for example the date of the analyses, who carried out the analyses, their qualifications, precise equipment/conditions employed and the raw data obtained. In particular since the porosity analyses had been carried out by a different laboratory it would in the Board's view have been necessary to provide information relating to the history, handling and conditioning of the samples employed in order to demonstrate that the samples subjected to analysis in the two laboratories were in all respects identical i.e. that no variations in handling occurred which could have influenced the analytical results of the respective sample portions analysed at the two laboratories.

3.5 The case law of the Boards of appeal sets a high threshold for proving public prior use. In particular it has to be established (cf. T 300/86 of 28 August 1989, not published in the OJ EPO, part 2.7 of the reasons; T 93/89, OJ EPO 1992, 718, part 8.1 of the reasons):

- What was made available,

- Where it was made available,

- When it was made available,

- How it was made available,

- By whom it was made available.

Further the case law identifies two levels or standards of proof to be applied - either the "balance of probabilities" or "up to the hilt". The standard of "balance of probabilities" is applicable when both parties involved, i.e. the patent proprietor and the opponent had access to the material of which public prior use is alleged (cf the above cited T 472/92, reasons 3.1). Although D5 appears to establish that the patent proprietor had access to a product of the grade designated D-KX412CS it has not been established that the patent proprietor had access to the specific batch of this product referred to in the letter of 7 August 2008, and as established by E2 the properties of D-KX412CS varied from batch to batch. Thus there is no basis for concluding that all batches of this product grade are identical. In circumstances where only one party had access to the material, public prior use of which is being alleged then a higher standard of proof is to be applied, namely "up to the hilt" (T 472/92, reasons 3.1).

3.6 Regarding the question of "what" was made available as explained above, the chain of evidence contains gaps. Although it has been established that product derived from a given production lot had been made available in a commercial transaction, and an analysis has been presented for a portion of product derived - at some unspecified point in time - from that production lot, as explained above, nothing is known about the history of the analysed portion of this production lot between production and analysis. It is, for example, not known:

- where this sample was found;

- in whose possession it had been in the intervening period of ca 12 years between production and the - presumed - date of analysis;

- under which conditions (e.g. heat/humidity) it had been stored during this period;

- no information has been provided which would permit it to be concluded that the particle size of the portion subjected to analysis was identical to that of the portion of the production batch which had been delivered according to the invoice.

Thus there exist a number of sources of doubt as to whether the portion of batch 660314 subjected to analysis was indeed identical to and representative of that portion of the indicated production batch which was the subject of the delivery witnessed by the invoice. Further doubts or uncertainties arise because, as explained above neither the original submission of 7 August 2008 nor the later written and oral submissions provide a complete record of the history and treatment of the sample or the analyses carried out or establish that, despite analyses being carried out in two different institutions, the samples of product submitted to analysis had undergone precisely the same history.

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3.7 In view of these uncertainties it is not possible to conclude, even on the "balance of probabilities", let alone "up to the hilt" that the sample subjected to analysis was necessarily identical to that product which was the subject of the delivery documented by the invoice. Accordingly the evidence submitted falls short of the standard required to establish that the product sold was identical to that according to the subject-matter of the operative claims.

3.8 Accordingly the allegation of lack of novelty due to public prior use of the product identified as "D-KX412CS" has not been proved.

3.9 Consequently it is concluded that the subject-matter of the patent-in suit meets the requirements of Art. 54 EPC.

4. The patent in suit, the technical problem

4.1 The patent in suit relates to a monoalkenyl aromatic compound/conjugated diene block copolymer composition for modifying asphalt. In particular an asphalt composition with high softening point, excellent ductility, excellent balance between physical properties, i.e. mechanical strength, workability and excellent storage stability is provided (patent in suit paragraphs [0001] and [0002]). The fields of use and demands placed on asphalt compositions are discussed in paragraphs [0003]-[0010] of the patent in suit. In particular it is taught that it is a challenge to provide polymer modified asphalt compositions which provide the desired use properties and also exhibit good workability (paragraphs [0008] and [0010]). According to paragraph [0013] it is intended to provide a polymer having excellent solubility in asphalt. According to paragraphs [0032]-[0034] the particle size distribution and pore volume of the polymer are of importance (features (f) and (g) of claim 1). In particular it is stated that if the content of larger particles - those remaining on a 5 mesh sieve - is too large, i.e. exceeds 30 % by weight the solubility becomes poor. Similarly if the content of smaller particles is too large - more than 30% by weight passing a 20 mesh sieve - then aggregation of particles can occur, meaning that a prolonged time for dissolution is required. Regarding the pore volume it is taught that if it is below 100mm**(3)/g incorporation of asphalt components becomes difficult and dissolution time is prolonged. If it is too high - above 2000mm**(3)/g - then the composition floats on the upper layer of asphalt meaning that dissolution takes longer. According to paragraph [0052] of the patent in suit the asphalt composition can be prepared by melt kneading the block copolymer with the asphalt.

4.2 Example 19 and comparative examples 9-13 of the patent in suit are based on the same starting polymer prepared by the method disclosed in Production Example 3. These examples subject the polymer to different post treatments in order to adjust the particle size distribution and porosity. According to the patent in suit, paragraph [0064] the solubility in asphalt is assessed by checking for the presence of undissolved matter employing a wire netting. The solubility is judged by the asphalt dissolution time when undissolved matter disappeared. The evidence of these examples can be summarised as follows:

- The polymer of example 19, which meets the requirements of claim 1 exhibits a dissolution time of 2.5 hours.

- The polymers of comparative examples 9 and 10, which have a proportion of small particles higher than that specified (40 and 80 wt% passing a 20-mesh sieve respectively) require dissolution times in excess of 5 hours.

- The polymers of comparative examples 11 and 13, having porosities of 94 and 70 mm**(3)/g respectively, i.e. below the minimum specified in operative claim 1 likewise require dissolution times in excess of 5 hours.

- The polymer of comparative example 12, having a content of large particles in excess of that specified in operative claim 1 (80 wt% remaining on a 5 mesh sieve) similarly exhibits a dissolution time in excess of 5 hours.

The evidence of the examples therefore demonstrates that the problem of improving the solubility of the polymer in asphalt as identified in paragraph [0013] of the patent in suit is solved by the claimed features, i.e. the particle size distribution and porosity.

4.3 The evidence of the examples of the patent in suit has been challenged by the appellant/opponent in the form of experimental report D12, submitted with a letter dated 6 July 2007. The speed of solubility had been assessed on the basis of torque, which it was explained reached a maximum when all the polymer had been dissolved. D12 showed that the particle size did not influence the solubility in the manner indicated by the examples of the patent in suit. The appellant/opponent also raised a number of criticisms with respect to the experimental methods employed by the respondent/patent proprietor. In the letter accompanying D12 it was, inter alia criticised that:

- Melt kneading was an inappropriate method due to the low viscosity of the bitumen employed. This would make the results unreliable;

- The poor solubility reported in the patent in suit in the case of small particle size compositions (Comparative examples 9 and 10) was postulated to be due to the fact that the material formed lumps, floating on the bitumen which were difficult to dissolve;

- The composition of comparative example 12 (high proportion of large particles) was submitted to be a fluffy grade; the processing steps employed in the patent in suit appeared to involve melting these particles, which, it was submitted, would be "devastating".

Subsequently, in the statement of grounds of appeal, the appellant/opponent emphasised that in the experiments reported in D12 the assessment of solubility had been carried out by the torque method which was a quantitative, proven method. The torque related directly to the amount of polymer dissolved with the consequence that the absence of any further change in the torque constituted proof that all polymer had dissolved. In contrast, the method employed by the patent proprietor in the examples of the patent in suit was "unreliable" employing a visual inspection which was highly dependent on the skill of the operator. Further sources of unreliability in the method employed by the patent proprietor were stated to arise since it was near impossible to determine the point of solubility of the pellets in bitumen (black, non-transparent). In the letter of 14 December 2009 (see section XII.(c), above) further submissions with respect to the experiments of the patent in suit were made, in particular it was submitted with respect to the problem of agglomeration that the different results obtained by the respondent/patent proprietor and appellant/opponent might be because the experiments of the patent in suit had been carried out under non-dispersing conditions whereas those carried out by the appellant/opponent had not. Similarly at the oral proceedings the criticism of the experiments of the patent in suit was pursued.

4.4 It is a fact that the results presented by the opposing parties are contradictory. It is also the case that, by its own admission, the appellant/opponent did not attempt to repeat the measurements as reported in the patent in suit but employed different measurement methods. Although it has been argued that the experiments of the patent in suit had been carried out under inappropriate conditions, which account for the - in the view of the appellant/opponent - anomalous results, it is conspicuous to the Board that the appellant/opponent has provided no evidence to support its contention in this respect. Specifically, the appellant/opponent has not provided any evidence that the results obtained would be critically affected by the manner of mixing employed (stated in the patent in suit to be melt kneading). Further the appellant/opponent has failed advance any reports relating to experiments that had been carried out in which the assessment of solubility was performed in the same manner as in the patent in suit and hence failed to provide any evidence in support of its contention that the methods employed were unreliable or would give rise to incorrect results. In fact all that the appellant/opponent has shown is that when carrying out both the mixing and measuring steps in a manner different from that disclosed in the patent in suit different results are obtained. It is also observed that oral submissions made by the appellant/opponent (see section XIII.(c) above) demonstrate that its written submissions in respect of the solubility measurements (D12) were incomplete, in particular in respect of whether or not a step of visual inspection had been carried out in the torque method to ensure that dissolution was complete. There is no reference to such a step in D12. Accordingly not only was information relating to these measurements given piecemeal but for this crucial aspect the relevant tests were only referred to orally, on the last possible day. No documentary confirmation of the experimental protocols actually employed, for example with respect to how the measurement methods had been validated with respect to the confirmation of full dissolution by viscosity measurements, was submitted. On the contrary the statements made by the appellant/opponent at the oral proceedings before the Board concerning the variability and subjectivity of the visual inspection method compared with the "reliable", "proven" torque method stand in obvious contrast to the statement made for the first time in its submissions dated 14 December 2009 i.e. shortly before the turn of the year and exactly one month prior to the date set for oral proceedings before the Board that the torque method had apparently been supplemented by a further check to confirm complete dissolution, which at the oral proceedings was clarified as being a visual inspection. Although reference was made to D3, page 3 in this context it is evident from the latter that the test methods are presented as alternatives, not as being mutually complementary. Thus there is an inconsistency in the presentation of the evidence which means that the appellant/opponent has failed to provide the information necessary and in time to allow the respondent/patent proprietor to replicate the manner in which the results reported by the appellant/opponent had been obtained and to put the Board in a position to assess and evaluate these experimental results with a view to understanding the reasons for the different outcomes obtained by the appellant/opponent and the respondent/patent proprietor.

4.5 Due to the incompleteness and inconsistency of the experimental evidence submitted by the appellant/opponent the Board can come to no other conclusion than that the entirety of the submissions of the appellant/opponent with respect to the alleged inappropriateness of the measurement methods employed in the examples of the patent in suit is unproven.

4.6 Thus the Board cannot accept this evidence as refuting the technical effect demonstrated by the experimental results in the patent in suit.

4.7 Accordingly it is concluded that the technical problem discussed above is effectively solved by the claimed subject-matter.

5. The closest prior art

5.1 D1, which is assigned to the present respondent/patent proprietor relates, like the patent in suit, to block copolymers intended fur use as modifiers for asphalt.

5.2 By common consent, this document represents the closest prior art.

5.3 As held in the decision under appeal, and not contested by either party (see section III.(c), above), the subject matter of the operative claims is distinguished from the disclosure of D1 by the features (f), the particle size distribution and (g), the pore volume.

5.4 As explained in the foregoing section 4, the available evidence, i.e. that of the patent in suit is that these features give rise to improvements with respect to the rate of solubility of the polymer in asphalt.

5.5 D1 itself is silent on the question of particle size and hence provides no incentive to adjust this feature for any reason, let alone specifically in order to optimise the solubility properties of the polymer in asphalt.

5.6 Although other documents contain discussions of the particle size, none of these teachings provides an indication of the specific particle size range required according to the operative claims:

5.6.1 D11 is a brochure relating to "Calprene® Rubbers". These polymers are stated to be radial teleblock , tetrabranched structures. However D11 does not disclose that the distribution of the blocks is as specified in operative claim 1. D11 further discloses (on the third page, right hand column) that the polymer has a particle size of 2-3mm crumbs. Further according to the following paragraph of D11 one grade - "Calprene 411" - has a "special granulometry and porosity" which improves the mixing with bitumen. However D11 contains no details about this "special granulometry", e.g. the particle size or porosity.

5.6.2 D3 is a product brochure relating to blending time of "Kraton D" polymers with bitumen. D3 teaches on page 3 that the morphology of the polymer has the greatest effect on blending times and that smaller particle size corresponds to a greater surface area and hence leads to shorter blending time. This teaching is contradicted by the evidence of the examples of the patent in suit, which, as explained above is that if the proportion of small particles is too high then the blending time is worsened.

5.7 The conclusion is that none of the prior art teaches the specific range of particle size now claimed and, insofar as the effect of particle size on blending time is mentioned in the prior art, this teaching leads away from the claimed invention. Accordingly it is concluded that the subject-matter of the operative claims is not obvious.

5.8 The requirements of Art. 56 EPC are therefore satisfied.