T 1798/22 - Inventive step of intermediate products

Key points

• " The [opponent /] appellant further put forward (also at the oral proceedings before the Board) that, considering that claim 1 of the patent in suit was directed to an ethylene polymer composition per se and not to a blend of polymers, the consideration whether D3 pointed towards the combination of two or more polymers was not relevant. Rather, what was to be considered was whether it would have been obvious, based on D3, to develop a polymer composition as defined in claim 1 of the patent in suit, with the aim of providing a composition which had good impact strength and optical properties, so the appellant"
• "[Based on the still leading decision T 65/82], As state of the art in relation to intermediates there are two different areas to be taken into account."
•  One is the "close-to-the-intermediate" state of the art. These are all compounds identified from their chemical composition as lying close to the intermediates. On the other hand the "close-to-the-product" state of the art must also be taken into account, i.e. those compounds identified from their chemical composition as lying close to the subsequent products."
• " With respect to the "close-to-the intermediate" state of the art, the question is whether or not the skilled man [the Board is citing T65/82] could have deduced from it the need to carry out certain purposive modifications to known compounds in order to obtain that intermediate which alone could enable him to solve the problem of making the subsequent products by means of a specific analogy process."
• T 65/82 r.12 adds: "Since the assumption is that this problem does not exist in the prior art, the answer must be in the negative, provided there is no compound already available which reacts in the same manner with substantially identical results. "
•  With respect to the "close-to-the product" state of the art, a further question then was whether or not the skilled man could have derived from it the claimed intermediate in an obvious fashion."
• As I understand it: the claimed intermediate I is used in the patent to make product P, the prior art teaches a similar compound P', the question is if the skilled person would, when trying to synthesize the known compound P', have used the same intermediate I. 
• " the Board considers that D3 does not constitute a relevant "close-to-the-product" state of the art (since it does not address at all the use as impact modifier and impact modified compositions) but rather that it could at most constitute a "close-to-the-intermediate" state of the art. "
• "However, since the problem of providing an impact modifier is not derivable from D3 itself, the answer to the question whether or not the skilled man could have deduced from it the need to carry out certain purposive modifications to known compounds in order to obtain that intermediate which alone could enable him to solve the problem of making the subsequent products can only be in the negative (see point 12 of the reasons of T 65/82)."
• The Board does not discuss the 'bonus effect' rule, perhaps this was not argued by the opponent, or perhaps this rule is not applicable in the context of T65/82, or perhaps this has to do with the fact that the Board dismisses D3 as not the closest prior art instead of holding the claim non-obvious over D3. 

EPO 

The link to the decision and an extract of it can be found after the jump.

https://www.epo.org/en/boards-of-appeal/decisions/t221798eu1

4. Inventive step

4.1 Closest prior art

4.1.1 In the decision under appeal, the opposition division considered that D3 was the most suitable document to be taken as the closest prior art (reasons: point 29). Some reference was further made in some instance to D2 as the closest prior art, which had also been relied upon by the opponent (reasons: points 29 and 32, in which it is in particular indicated that a similar argumentation applies to D2).

4.1.2 In their statement of grounds of appeal, the appellant substantiated an objection of lack of inventive step in view of D3 as the closest prior art and further indicated that the same arguments applied equally to D2 and D5 (statement of grounds of appeal: point 18 on page 16).

a) However, the appellant confirmed at the oral proceedings before the Board that they had no different line of attack starting from D2 and D5, so that only the attack starting from D3 had to be decided upon, the same conclusion being bound to be equally valid for the objections starting from D2 and D5 (minutes of the oral proceedings, page 3, second paragraph). For that reason, only the objection based on D3 as the document constituting the closest prior art needs to be dealt with in the present decision.

b) Also, in view of the (for the respondent) positive decision on inventive step reached by the Board, there is no need to address the issue of the admittance into the proceedings of the objection of lack of inventive step starting from D5 as the closest prior art, which was mentioned in the Board's communication (point 7.1.2.a).

4.1.3 Regarding the selection of D3 as the document constituting the closest prior art, the respondent put forward that D3 would not be reasonably considered as a suitable starting point for the analysis of inventive step because it did not deal with the technical problem addressed by the patent in suit, namely to provide an ethylene polymer composition to be used as an impact modifier (rejoinder: page 19, section 4.2).

a) In the Board's view, it makes no doubt that such an objection was already put forward by the respondent during the opposition proceedings (see e.g. reasons: point 28). However, although the opposition division addressed that concern in their reasoning (reasons: point 29), it is not clear to the Board why they eventually decided to consider that D3 was a suitable document to be taken as the closest prior art. The fact that D3 "discloses at least similar technical effects mentioned" (reasons, point 29, first sentence) appears in that respect in contradiction with the fact that "D3 does not mention the use of similar compositions for use as an impact modifier" (reasons, point 29, second sentence) or with the fact that the patent in suit discloses the use of the compositions according to claim 1 as granted as impact modifier for another polymer (reasons: page 18, first paragraph).

b) In view of that passage of the decision and of the appellant's arguments (statement of grounds of appeal: points 19-24 on pages 16-18), the question arose if the selection of D3 as the closest prior art was reasonable or if it should be rejected because it was based on hindsight.

c) In that regard, according to established case law (Case Law, supra, I.D.3.3), a document serving as the starting point for evaluating the inventive merits of an invention should relate to the same or a similar technical problem or, at least, to the same or a closely related technical field as the patent in suit.

d) In the present case, it remained undisputed that the main problem addressed in the patent in suit, namely the preparation of an ethylene polymer composition that can be suitably used as impact modifier (patent in suit: paragraphs 1-5; see also claims 1, 8 and 10 as granted) is not addressed at all in D3, which is rather directed to the preparation of films that already have high impact strength (D3: all claims; paragraphs 1 and 9; examples 5 and 8). In the Board's view, the appellant's argument that the skilled person would consider the compositions of D3 as potential impact modifiers, even without a specific disclosure to this effect in D3 (statement of grounds of appeal: point 22 on page 17, last sentence; oral proceedings before the Board), is not supported by any evidence and for that reason, is not convincing.

e) Additionally according to the case law (Case Law, supra, I.D.3.3, see in particular the paragraph on T 644/97) a technical problem arising from a "closest prior art" disclosure which is irrelevant to the claimed subject-matter (in the sense that it did not mention a problem that was at least related to that derivable from the patent specification) had a form such that its solution could practically never be obvious, because any attempt by the skilled person to establish a chain of considerations leading in an obvious way to the claimed subject-matter was bound to fail. In the Board's view, the latter case law is applicable to the present case: since the (relevant) problem addressed in the patent in suit is not derivable from D3, nor is a problem mentioned in D3 which is at least related to it, the measures for its solution cannot be derivable in an obvious manner therefrom.

4.1.4 The appellant further put forward (also at the oral proceedings before the Board) that, considering that claim 1 of the patent in suit was directed to an ethylene polymer composition per se and not to a blend of polymers, the consideration whether D3 pointed towards the combination of two or more polymers was not relevant. Rather, what was to be considered was whether it would have been obvious, based on D3, to develop a polymer composition as defined in claim 1 of the patent in suit, with the aim of providing a composition which had good impact strength and optical properties, so the appellant (statement of grounds of appeal: point 23 on page 17).

a) With regard to that argument, the Board considers that, as was indicated in the Board's communication (section 7.1.5), the established case law regarding inventive step of intermediate products (Case Law, supra, 9.9.4) is relevant to the present case, as the polymer composition of claim 1 can be seen as the intermediate of the final impact modified composition. In that respect, the findings of decision T 65/82 (OJ 1983, 327) are particularly relevant. They may be summarised as follows (see Headnotes II-IV of T 65/82):

As state of the art in relation to intermediates there are two different areas to be taken into account. One is the "close-to-the-intermediate" state of the art. These are all compounds identified from their chemical composition as lying close to the intermediates. On the other hand the "close-to-the-product" state of the art must also be taken into account, i.e. those compounds identified from their chemical composition as lying close to the subsequent products. With respect to the "close-to-the intermediate" state of the art, the question is whether or not the skilled man could have deduced from it the need to carry out certain purposive modifications to known compounds in order to obtain that intermediate which alone could enable him to solve the problem of making the subsequent products by means of a specific analogy process. With respect to the "close-to-the product" state of the art, a further question then was whether or not the skilled man could have derived from it the claimed intermediate in an obvious fashion.

b) In that regard, the Board considers that D3 does not constitute a relevant "close-to-the-product" state of the art (since it does not address at all the use as impact modifier and impact modified compositions) but rather that it could at most constitute a "close-to-the-intermediate" state of the art. However, since the problem of providing an impact modifier is not derivable from D3 itself, the answer to the question whether or not the skilled man could have deduced from it the need to carry out certain purposive modifications to known compounds in order to obtain that intermediate which alone could enable him to solve the problem of making the subsequent products can only be in the negative (see point 12 of the reasons of T 65/82).

c) Although that analysis was communicated to the parties in the Board's communication (section 7.1.5), no counter-arguments were put forward by the appellant to refute that view (either in their written submission dated 27 June 2024 or at the oral proceedings before the Board). Therefore, there is no reason for the Board to deviate from its preliminary considerations.

4.1.5 Under these circumstances, the Board considers that D3 does not constitute a suitable document to be taken as the closest prior art. As a consequence, the appellant's objection based on D3 as the document constituting the closest prior art is to be rejected already for that reason.

4.1.6 Although the Board arrived at the conclusion that even if D3 were considered as a reasonable document to be taken as the closest prior art, the subject-matter of claim 1 as granted would not be obvious (for the reasons indicated in sections 7.2 to 7.4 of the communication of the Board, even considering the arguments put forward by the appellant in their further written submissions or at the oral proceedings before the Board), there is no need for the Board to provide any reasoning in that regard in view of the above conclusion that D3 does not constitute a reasonable starting point for the analysis of inventive step.

4.1.7 For these reasons, the Board is satisfied that claim 1 as granted involves an inventive step having regard to document D3. In addition, as indicated above (section 4.1.2), that conclusion is equally valid having regard to either D2 or D5.

4.1.8 In view of the above, the subject-matter of claim 1 as granted involves an inventive step over the available prior art.

5. As none of the objections put forward by the appellant against the main request is successful, the appeal is to be dismissed.