Thursday 25 November 2010

T 1397/07 – Silence Won’t Deter


[7.1] According to the established jurisprudence of the Boards of Appeal it is necessary, in order to assess inventive step, to establish the closest state of the art, to determine in the light thereof the technical problem which the invention addresses and successfully solves, and to examine the obviousness of the claimed solution to this problem in view of the state of the art. This “problem-solution approach” ensures assessing inventive step on an objective basis and avoids an ex post facto analysis. The closest prior art is normally a prior art document disclosing subject-matter aiming at the same objective as the claimed invention and having the most relevant technical features in common. 

[7.2] The patent in suit is directed to a process for dimerising an olefinic feedstock with high selectivity to the dimer […]. A similar process already belongs to the state of the art in that document D6 discloses a process for dimerising isobutene having all the features of present claim 1 apart from the location of the side draw […], wherein said dimerisation is enhanced and further oligomerisation is suppressed […]. 

[7.2.1] The [patent proprietor] submitted that document D10 represented the closest prior art, since it was more recent than document D6, but conceded that in view of the absence of a side draw in any distillation column disclosed in document D10, document D6 had more technical features in common with the claimed invention. The Board notes, however, that A 56 requires the assessment of inventive step to be made “having regard to the state of the art”, A 54(2) defining the state of the art “to comprise everything made available to the public”, without addressing any time frame (see T 113/00 [3.7]). As a consequence, there is no legal basis in the EPC to preclude a particular state of the art, in the present case document D6, from being taken into account when assessing inventive step, merely because of being published some years earlier than another one. Furthermore, no technical reason has been submitted as to why the skilled person would disregard document D6 for the only reason that its publication date lies further in the past than that of document D10.

[7.2.2] Thus, the Board considers, in agreement with the [opponent], that in the present case the process of document D6 […] represents the closest state of the art and, hence, takes it as the starting point when assessing inventive step. 

[7.3] In view of this state of the art, the [patent proprietor] submitted that the problem underlying the patent in suit was the provision of a more versatile process in order to make more oxygenates available for the process. 

[7.4] As the solution to this problem, the patent in suit according to the auxiliary request I proposes that the at least one flow comprising oxygenate is withdrawn from the side of at least one distillation column from a plate higher than the feed plate. 

[7.5] Said solution thus covers processes wherein MTBE is the oxygenate. However, MTBE is the oxygenate used in the process according to the closest document D6. Thus, at least insofar as the oxygenate is MTBE, the claimed process cannot be more versatile than that of document D6, with the consequence that the purported improvement cannot be achieved for this embodiment. 

[7.6] Since in the present case the alleged advantage, i.e. improved versatility of the process with respect to the oxygenate, is not achieved throughout the entire ambit of the claimed subject matter, the technical problem […] needs to be redefined in a less ambitious way. In view of the teaching of document D6, and as conceded by [patent proprietor] in the oral proceedings (OPs) before the Board, it can merely be seen in the provision of an alternative process for dimerising olefin feedstocks (see T 939/92 [2.5.4]). 

[7.7] Finally, it remains to be decided whether or not the proposed solution to the problem underlying the disputed patent is obvious in view of the cited prior art. 

[7.7.1] Document D6 embraces merely two possibilities for the positioning of the side draw in the distillation column, namely above or below the feed plate, there being no other conceivable configuration, as agreed by both parties. Hence, withdrawing the side stream at a plate above the feed plate is neither critical nor a purposive choice from within the teaching of document D6 for solving the objective problem underlying the patent in suit, since no unexpected effect has been shown to be associated with this position of withdrawal vis-à-vis the only other possibility. The act of positioning the side draw above the feed plate is thus within the routine activity of the skilled person faced with the mere problem of providing an alternative process for dimerising olefin feedstocks. Therefore, the arbitrary choice of withdrawing the oxygenate-containing side stream from a plate higher than the feed plate cannot provide the claimed process with any inventive ingenuity. 

[7.8] For the following reasons the Board cannot accept the [patent proprietor]’s arguments designed for supporting inventive step. 

[7.8.1] The [patent proprietor] submitted that the skilled person would have been deterred from locating the side stream above the feed plate, there being no pointers in document D6 to placing the side draw above, but rather strong pointers to placing it below the feed. More particularly, there was no teaching in document D6 that MTBE could be present in the distillation column above the feed. On the contrary, since it was indicated at column 2, line 55 that the MTBE and oligomers were withdrawn as a bottoms product, and in claim 12 that a diisobutene fraction containing MTBE was recycled to the reactor, dimers/oligomers being heavy products, the skilled person, wishing to recycle a stream high in MTBE and containing some oligomers would have placed the side draw towards the bottom of the column, and thus, below the feed plate, in order to be sure of withdrawing an MTBE-containing stream.

However, there is no specific teaching in document D6 regarding the positioning of the side draw with respect to the feed plate, the lack of a specific positive teaching to place the side draw above the feed plate not being tantamount to a deterrent. 

Indeed such a teaching, had it been present, would have rendered said document novelty destroying for the presently claimed process. The skilled person thus takes the teaching of document D6 at face value, which means that he would have expected that all processes described specifically therein, as well as those processes falling within the general teaching thereof, would have been suitable for dimerising an olefin feedstock. 

Thus even if there had been a hint in another document discouraging the skilled person from positioning the side draw above the feed, the skilled person would still have expected all processes within the teaching of document D6, including that of positioning the side draw above the feed, to successfully dimerise an olefinic feedstock. 

Nothing was submitted by the [patent proprietor] from which the Board could reasonably conclude that the skilled person has been deterred from following the straight teaching of that document, such that the [patent proprietor’s] arguments do not convince the Board. 

With regard to there being no teaching in document D6 that MTBE could be present in the distillation column above the feed, when assessing inventive step it is not necessary to establish that the success of an envisaged solution of a technical problem was predictable with certainty. In order to render a solution obvious it is sufficient to establish that the skilled person would have followed the teaching of the prior art with a reasonable expectation of success (see decisions T 249/88 [8]; T 1053/93, [5.14]).

In the present case, the Board cannot agree with the [patent proprietor]’s argument that due to some purported uncertainty about the predictability of success, the skilled person would not have contemplated locating the side draw above the feed plate in order to merely provide an alternative process for dimerising olefin feedstocks, particularly when said alternative falls within the teaching of document D6. It was only necessary for him to confirm experimentally by routine work that placing the side draw above the feed plate in that process embodiment of document D6 […] indeed resulted in a successful process for dimerising olefin feedstocks, thus arriving at the claimed invention without inventive ingenuity. 

Finally, with regard to the alleged pointers toward placing the side draw below the feed, the two passages in document D6 referred to by the [patent proprietor] […] do not describe the embodiment in this document which is the closest to the presently claimed process, […] wherein it is specified that the first distillation may be carried out with an intermediate draw stream in the distillation column which can be recycled to the oligomerisation reaction. 

 In both passages referred to by the [patent proprietor], this first distillation is carried out without withdrawal and recycling of a side stream, such that any teaching which may be derived therefrom is not relevant to the closest prior art embodiment which is the starting point in the assessment of inventive step. 

[7.8.2] The [patent proprietor] also submitted that although the skilled person could have adapted the process according to document D6 and thereby arrived at something falling within the terms of the claims, he would not necessarily have done so.  

However, if the problem is merely the provision of an alternative process, the skilled person would modify the process according to document D6 in any way that he could, particularly, when, as in the present case, said modification lies within the general teaching of said document […]. 

[7.8.3] Finally, the [patent proprietor] submitted that the commercial success of the claimed process as witnessed by the significantly lower investment costs required therefor supported the presence of an inventive step. 

However, according to established case law commercial success alone is not to be regarded as indicative of inventive step. Such secondary indicia are no substitute for the assessment of inventive step vis-àvis the state of the art on an objective basis following the “problem-solution approach”. 

Secondary indicia represent auxiliary considerations for the assessment of inventive step and are only relevant in cases of doubt when the objective evaluation of the prior art has not provided a clear picture (see decisions T 24/81 [15]; T 351/93, [5.6]; T 645/94 [4.7]).

In the present case, however, there are no doubts as to the absence of an inventive step, since the objective evaluation of the state of the art following the “problem-solution-approach” gives a clear picture, albeit a negative one […]. In any case, it has not been shown that any purported economical advantages of the claimed process are causally linked to the distinguishing feature of the invention, namely the specific location of the side draw and for that reason too, this argument is not convincing. 

[7.9] For these reasons, the solution proposed in claim 1 to the problem underlying the patent in suit is obvious in the light of the prior art. 

[8] As a result, the Appellant’s auxiliary request I is not allowable for lack of inventive step pursuant to A 56. 

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