No. of citations: 146
T 20/81 looked at a case where the applicant based its inventive step argumentation on alleged advantages of his invention over the prior art; the alleged advantages, however, were not demonstrated by the evidence presented.
Claim 1 of the underlying application related to a process for the preparation of meta-aryloxy-benzaldehydes by reaction of a mixture of the corresponding meta-aryloxybenzyl halides and meta-aryloxy-benzal halides with hexamethylene tetramine followed by hydrolysis of the resulting products.
The Examining Division refused the application for lack of inventive step over Dutch patent application NL-A-7 701 128 and a textbook chapter (Organic Reactions Vol. III, 1954, John Wiley, New York, Chapter 4, S. H. Angyal). The process disclosed in NL-A-7 701 128 used acid in the reaction mixture, which required the use of acid-resistant reaction vessels. The applicant formulated the technical problem as lying in the provision of an improved process, which avoids the negative effects of the acid in the reaction mixture. The argument, however, did not convince the Examining division.
In appeal, the appellant-applicant reformulated the technical problem. According to the appellant, the problem was not simply to eliminate the disadvantages emerging from the use of an acid in the process of the NL-A-7 701 128, but to generally improve the known process for preparing meta-phenoxy benzaldehyde. Based on a comparative example (example 5), he claimed that the claimed process could be carried out in less time and at a slightly higher yield.
The Board commented as follows:
"Moreover, the applicant refers to the advantage that hydrolysis can now be carried out in a shorter time to obtain a slightly higher yield of POAL (page 2, lines 10-12). This advantage is said to be proven by the results of the comparative example within example 5 on file. Contrary to the submission of the applicant, the comparison is not pertinent, since different temperatures were used, namely 110° C for the hydrolysis step pursuant to the present application, but only 106°C for that of the old Shell process. It is well known that the employment of different reaction temperatures entails a different speed of reaction. In general, a rise of temperature by 10°C will cause the speed to double or triple." (point 3 of the reasons)The Board thus carefully compared the claimed process with the process described in comparative example 5 and found that the alleged advantages, on which the appellant-applicant relied, were not proven by those experiments.
The Board drew the following conclusion:
"Consequently, the conclusion must be drawn that the additional advantages referred to by the appellant have not been properly demonstrated. Such alleged but unsupported advantages cannot be taken into consideration in respect of the determination of the problem underlying the application. For this reason, the problem the applicant must have faced remains the one already defined." (point 3 of the reasons)Applying the former technical problem, the Board agreed with the Examining Division's conclusion that the claimed process did not involve an inventive step.
The appeal was rejected.
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Headnote:
In order to render them relevant to the definition of the problem underlying the invention, and hence to the assessment of inventive step, alleged advantages should be supported by sufficient evidence where comparison is made with highly pertinent prior art.The full text of the decision can be accessed here.
See also T 181/82 on a related issue.
