T 1666/16 - Angle of repose

Key points

• Claim 1 is directed to a powder defined by chemical features (composition) and properties features such as a particle size distribution, a bulk density, and an angle of repose.
• “ The [opponent] also argued lack of novelty of granted claim 1 over the alleged public prior uses based on a sale of the product SOLEF®PVDF 1010/1001 by Solvay to SGL ACOTECH GmbH in 2003”
• “Furthermore, the angle of repose determined in the experimental report submitted by the appellant is a property dependent on the structure of the powder, but does not constitute per se a structural definition thereof. The Enlarged Board specified in point 3 of the reasons for the opinion G 1/92 (supra) that a commercially available product per se does not implicitly disclose anything beyond its composition or internal structure. Extrinsic characteristics, which are only revealed when the product is exposed to interaction with specifically chosen outside conditions, e.g., reactants or the like, in order to provide a particular effect or result or to discover potential results or capabilities, therefore point beyond the product per se as they are dependent on deliberate choices being made. This is the case for the angle of repose which therefore cannot be considered to have been known at the date of sale of the products whose public prior use is invoked by the appellant.”
• I'm not sure if I agree with this reasoning. If the powder of the public prior use inherently had the property, specifying that property in a product claim should not provide novelty in my view (with an exception of course for second medical use claims). 

T 1666/16 -

https://www.epo.org/law-practice/case-law-appeals/recent/t161666eu1.html

II. The European patent was granted on the basis of 15 claims, claim 1 reading as follows:

"1. Polyvinylidene fluoride resin powder for melt molding having such powder characteristics (a) to (c) that

(a) the resin powder exhibits, as determined by a dry sieving method in accordance with JIS K 0069, such particle size distribution characteristics that

i) an average particle diameter indicated by a 50% cumulative value (D50) in a particle size cumulative distribution is 80 to 250 µm,

ii) a proportion of resin powder having a particle diameter of at most 45 µm is at most 3.0% by weight,

iii) a proportion of resin powder having a particle diameter of at least 355 µm is at most 5.0% by weight, and

iv) a value [(D80 - D20)/D50] obtained by dividing a particle diameter breadth (D80 - D20) represented by a difference between a 80% cumulative value (D80) and a 20% cumulative value (D20) in the particle size cumulative distribution by the 50% cumulative value (D50) is at most 0.8,

(b) a bulk density is 0.40 to 0.70 g/cm3 as determined by a measuring method for Bulk Specific Gravity in accordance with JIS K 6721-3.3, and

(c) an angle of repose is at most 35° as determined by a measuring method described in the specification in which a bulk specific gravity measuring device prescribed in JIS K 6721 is used."

Novelty over the alleged public prior uses

9. The appellant also argued lack of novelty of granted claim 1 over the alleged public prior uses based on a sale of the product SOLEF®PVDF 1010/1001 by Solvay to SGL ACOTECH GmbH in 2003 and on a sale of the product SOLEF®PVDF 1015/1001 by Solvay to PCI Membrane Systems Ltd in October 1993. The respondent did not challenge the finding of the opposition division in points 4.3.3 and 4.4.2 of the reasons for the contested decision that these sales took place before the priority date of the patent at issue. The Board has no reason to take a different view. The respondent, however, argues concerning the sale of SOLEF®PVDF 1010/1001 in 2003 that it is highly questionable whether the long storage time of a sample of the product manufactured in 2002, the analysis of said sample only being made in 2012, had no influence on the properties measured, especially on the angle of repose. In respect of the sale of SOLEF®PVDF 1015/1001 in 1993 the respondent also argues that the experimental data provided with E9 and E10 concern products manufactured in 2002 and are not relevant to determine the nature of the product sold in 1993. Moreover, the respondent argues in view of the rationale of opinion G 1/92 of the Enlarged Board of Appeal (OJ EPO 1993, 277) that the products SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001 could not have been made available to the public, since it had not been shown that those products could be reproduced without undue burden by the skilled person.

9.1 In opinion G 1/92 the Enlarged Board of Appeal held that the chemical composition of a product forms part of the state of the art when the product as such is available to the public and can be analysed and reproduced by the skilled person, irrespective of whether or not particular reasons can be identified for analysing the composition. The same principle applies mutatis mutandis to any other product (points 1 and 2 of the Conclusion). It also stated in point 1.4 of the Reasons for the Opinion that "An essential purpose of any technical teaching is to enable the person skilled in the art to manufacture or use a given product by applying such teaching. Where such teaching results from a product put on the market, the person skilled in the art will have to rely on his general technical knowledge to gather all information enabling him to prepare the said product. Where it is possible for the skilled person to discover the composition or the internal structure of the product and to reproduce it without undue burden, then both the product and its composition or internal structure become state of the art".

Composition / internal structure of SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001

9.2 Concerning the nature of the products SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001, the submissions of the appellant were based on the experimental report attached to declarations E9 to E11. These reports indicate for each of the parameters defined in operative claim 1 the corresponding values for SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001, i.e. the values of the bulk density and of the angle of repose, as well as the values determined by a dry sieving method of D50, D80 and D20, the proportion of resin powder having a particle diameter of below 45 µm and the proportion of resin powder having a particle diameter of more than 355 µm. In addition, values of D50, (D80 - D20)/D50 and the proportion of resin powder having a particle diameter of below 45 µm and the proportion of resin powder having a particle diameter of more than 355 µm were also determined by laser diffraction.

As to the experimental report attached to E15, this evidence concerns an unspecified sample of SOLEF®PVDF 1015/1001, i.e. a sample which has not been indicated to be representative of the properties of the powder prepared at the time the alleged public prior uses concerned took place. The purpose of this experimental report is to demonstrate the validity of the methodology used in E9 to E11. In any event, it does not address further characteristics in addition to those already addressed in the experimental report attached to E9 to E11. The Board also notes that Mr Roblot provided with his testimony during the oral proceedings before the opposition division a vague statement concerning the viscosity of the products of type 1010 and a vague indication concerning the average diameter of the powder of product (minuted testimony, page 5/23, last paragraph and page 8/23, penultimate paragraph, respectively).

Furthermore, the angle of repose determined in the experimental report submitted by the appellant is a property dependent on the structure of the powder, but does not constitute per se a structural definition thereof. The Enlarged Board specified in point 3 of the reasons for the opinion G 1/92 (supra) that a commercially available product per se does not implicitly disclose anything beyond its composition or internal structure. Extrinsic characteristics, which are only revealed when the product is exposed to interaction with specifically chosen outside conditions, e.g., reactants or the like, in order to provide a particular effect or result or to discover potential results or capabilities, therefore point beyond the product per se as they are dependent on deliberate choices being made. This is the case for the angle of repose which therefore cannot be considered to have been known at the date of sale of the products whose public prior use is invoked by the appellant.

9.3 As to the internal structure of the powders sold, whereas determining the chemical nature and composition of a PVDF powder is straightforward, a description of its structure is not a trivial task. Such PVDF powders can be described at several scales. At the largest scale the structure of the powder can be defined by the various particles constituting the powder, which particles differ in size, possibly also in shape and in the morphology of their surface. The experimental report attached to E9 to E11 contains information concerning only the particle size distribution characteristics (a) i) to iii) as defined in operative claim 1, which characteristics do not represent a full description of the particle size distribution of the powder measured. Moreover, at a smaller scale the complex structure of this polymer is defined by that of its various chains, e.g. molecular weight and distribution thereof, chain configuration, orientation. It is in this respect referred to D4 (page 4, second paragraph of section 2.2, lines 1-7) which is an excerpt of an encyclopedia concerning PVDF resins and therefore can be considered to reflect the general knowledge in the art.

9.4 On that basis it is concluded that the information provided by the appellant is not sufficient to characterize the internal structure of the products SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001. In the absence of additional submissions in this respect, the appellant did not demonstrate that the skilled person would have been able to determine the internal structure of the products whose public prior use is invoked.

Ability to reproduce SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001

10. The appellant did not argue that information about the processes actually used for manufacturing SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001 was available to the public, but essentially argued that the skilled person based on the common general knowledge in the art would have been able to produce the powders whose sale occurred. Even if to the benefit of the appellant one could assume that the skilled person would recognize that such products had been produced by suspension polymerisation, the skilled person would still be faced with the difficulty that the complex structure of a specific powder, including the structure of the polymer at the molecular scale, depends on the various conditions used for its synthesis (see above points 4.5 and 9.3). The absence of precise structural information concerning SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001 does not allow any conclusion as to whether these two specific types of powder, which in fact can only be accurately defined in a complex way as shown above, could necessarily be reproduced without undue burden, i.e. with reasonable effort. Evidence that the skilled person using common general knowledge and only a reasonable amount of experimentation would be generally able to reproduce PVDF resin powders was also not submitted. The sole information concerning the synthesis of PVDF powders referred to by the appellant was that contained in D1 and D3 which are two patent applications whose specific teaching cannot be considered to represent the common general knowledge in the art.

11. Accordingly, based on the appellant's submissions, the Board cannot conclude that the skilled person would have been able to determine the internal structure of SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001 and to reproduce those without undue burden at the date of their sale. Under those circumstances and in view of the requirements set out in opinion G 1/92 for the internal structure of a product put on the market before the priority/filing date of the patent to be considered to have been made available to the public, it is concluded that the internal structure of SOLEF®PVDF 1010/1001 and SOLEF®PVDF 1015/1001 did not form part of the prior art pursuant to Article 54(2) EPC. Accordingly, the public prior uses invoked by the appellant cannot anticipate the subject-matter of claim 1.