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I.D.6. Expectation of success, genetic engineering and biotechnology
In accordance with the case law of the boards of appeal, a course of action could be considered obvious within the meaning of Art. 56 EPC 1973 if the skilled person would have carried it out in expectation of some improvement or advantage (T 2/83, OJ 1984, 265). In other words, obviousness was not only at hand when the results were clearly predictable but also when there was a reasonable expectation of success (T 149/93).
In some decisions in the field of genetic engineering the board asked whether in the cases in point it was obvious for the skilled person to try a suggested approach, route or method with a reasonable expectation of success (T 60/89, OJ 1992, 268). For more about biotechnological inventions and the definition of the skilled person, see Chapter I.D.7.1.3.
In T 296/93 the board held that, in relation to inventive step, the fact that other persons or teams were working contemporaneously on the same project might suggest that it was "obvious to try" or that it was an interesting area to explore, but it did not necessarily imply that there was a "reasonable expectation of success". A reasonable expectation of success should not be confused with the understandable "hope to succeed"; it implied the ability of the skilled person to predict rationally, on the basis of the knowledge existing before a research project was started, the successful conclusion of the said project within acceptable time limits. The more unexplored a technical field of research was, the more difficult it was to make predictions about its successful conclusion and, consequently, the lower the expectation of success (T 694/92, OJ 1997, 408). According to T 207/94 (OJ 1999, 273), the "hope to succeed" was merely the expression of a wish, whereas a "reasonable expectation of success" presupposed scientific appraisal of available facts.
In T 187/93 it was stated tha,t even if it was obvious for the skilled person to try an experiment, it was not necessarily true that this person would have any reasonable expectation of success when embarking on it.
In T 223/92 the board said that in 1981, given the state of the art at that time, the skilled person would have opted for DNA-recombination technology only if relying, e.g., on his own good luck and inventiveness to overcome the known (and as yet unknown) problems involved, which would have caused the average skilled person to expect to fail.
In a few cases, the board stated that there have been cases where inventive step was denied by the boards of appeal because the skilled person was in a "try and see" situation. Such a situation was considered to have occurred if the skilled person, in view of the teaching in the prior art, had already clearly envisaged a group of compounds or a compound and then determined by routine tests whether such compound/s had the desired effect (T 889/02, T 542/03, T 1241/03, T 1599/06). In T 91/98 the board stated that the rationale behind the "reasonable expectation of success" approach is that one may easily conceive of inventions to be made by genetic engineering, yet realising them may cause problems in view of difficulties known or experienced when starting the project. In the case before the board, in order to find out whether derivatives of azidothymidine had an activity against human retroviruses while remaining non toxic to cells, it was enough to perform well‑known, routinely carried‑out in vitro tests of viral infectivity, so it was rather a "try and see" approach which applied.
In T 1396/06 the board stated that a skilled person, even when applying routine methods with the aim of solving a closely related technical problem, would not have the absolute certainty of succeeding. However, certainty of success is not required according to the jurisprudence of the boards of appeal, which makes a clear distinction between reasonable expectation of success and certainty of success (T 918/01). Rather, in spite of the understandable uncertainties which always characterise biological experiments, the skilled person would have had no reason to adopt a sceptical attitude. He would have had either some expectations of success or, at worst, no particular expectations of any sort, but only a "try and see" attitude, which does not equate with an absence of a reasonable expectation of success (see also T 759/03).
In T 111/00 the board noted that this approach was intended in particular to take into account the complexity inherent in some recombinant DNA techniques, which might jeopardise the final outcome of experiments making use of them. In the case at issue, the skilled person would have considered the cloning of human cDNA as a matter of routine since the necessary probe was available from document 1 and no problems were encountered.
In the light of the closest prior art the board saw the technical problem to be solved in T 886/91 in the exact identification and characterisation of DNA sequences of HVB genome subtype adyw. The board pointed out that the situation in T 886/91 could not be compared with the one in T 223/92 and T 500/91, where production of a partially known protein in a recombinant-DNA system was achieved and considered inventive on the basis of the fact that, in the specific circumstances of those cases, there was no realistic expectation of success. In the case in point the closest prior art had already disclosed the cloning and expression of the HBV genome subtype adyw. The identification and characterisation of the claimed specific sequences of the same genome involved for the skilled person nothing more than the performance of experimental work by routine means in connection with the normal practice of filling gaps in knowledge by the application of existing knowledge.
In T 923/92 (OJ 1996, 564) the board had to decide whether the skilled person would have attempted, with reasonable expectation of success, to produce cDNA coding for human t-PA, or whether in this instance he would have known from his technical knowledge, before even embarking on the research, that he would be able to complete his project within an acceptable time. The board bore in mind that, as stated in T 816/90, "even when it is possible to theoretically conceive a straightforward approach to solve a specific technical problem, the skilled person might be confronted with unexpected difficulties when trying to put the conceived strategy into practice". The board stated that, although hoping to succeed, the skilled person embarking on this project would have known that its successful conclusion depended not only on technical skill in putting into practice the sequence of precise steps of the theoretical experimental protocol, but to a large extent also on the ability to take the right decisions along the way whenever a difficult experimental situation so required. Under these circumstances, it could not be said that the skilled person had a reasonable expectation of success.
In T 386/94 (OJ 1996, 658), again citing T 816/90, the board ruled that, in gene technology, inventive step could not be acknowledged if, at the priority date, a skilled person could expect to perform the cloning and expression of a gene in a fairly straightforward manner, and the cloning, although requiring much work, did not pose such problems as to prove that the expectation of success was ill-founded.
Where the expression of a cloned DNA in a chosen foreign host constituted the subject-matter of the claimed invention, the question whether a reasonable expectation of success existed or not could be evaluated only by taking into account real difficulties relating to that step. Thus, in order to be considered, any allegation that features jeopardised a reasonable expectation of success had to be based on technical facts (T 207/94, OJ 1999, 273).
In T 737/96 the board was of the opinion that it was not appropriate to attempt to evaluate the expectation of success of a random technique such as mutagenesis where results depended on chance events. This was because the skilled person knew that, unless a specific selection method could be developed, which was not the case in the patent in suit, perseverance and chance played a key role in achieving success, as no form of control could be exerted over the mutation events. Under these circumstances, as in a lottery game, the expectation of success always ranged irrationally from nil to high, so it could not be evaluated in a rational manner based on technical facts. This was at variance with technical situations in which more predictable methods were relied upon to solve a particular problem, such as methods of genetic engineering like cloning or expressing a DNA sequence. In such situations, it was often possible to make rational predictions about the likelihood of success, and "reasonable expectation of success" was then a meaningful and reliable criterion for assessing inventive step (see also T 694/92, OJ 1997, 408).