1. The plausibility ab initio of the case-law I. This decision concerns the appeal of the opponent (appellant) against the decision of the Opposition Division (contested decision) to reject the opposition to European patent No 2 484 209 (patent at issue). It can therefore be concluded that the synergistic effect described in the patent at issue for Plutella xylostella and Spodoptera litura is not achieved over the entire width of claim 1. The board also stated in its decision that under Article 56 EPC, an inventive step is recognised if, according to the state of the art, the invention would not have been obvious to a person skilled in the art. The board noted that the strict criterion of “plausibility ab initio” does not take into account the content of the prior art, although it is used to assess inventive step, so that this criterion cannot be provided for in Article 56 EPC. `According to the settled case-law of the Boards of Appeal, the assessment of inventive step at the date of entry into force of the patent must be carried out on the basis of the information contained in the patent and of the common general knowledge available to the person skilled in the art at that time. Evidence published subsequently that the claimed subject-matter solves the technical problem that the patent at issue purports to solve may be taken into account if it is plausibly apparent from the disclosure of the patent that the problem has actually been resolved (see Case Law of the Boards of Appeal, 8th edition, I.D.4.6; T 1329/04, reasons 12; T 1043/10, No. 12 or [sic] reasons for decision).
In order for the evidence subsequently published to be taken into account, it is therefore necessary to determine whether the alleged activity for dasatinib was sufficiently plausible at the time of entry into force of the patent at issue. This assessment shall be based on the application as filed and on the general knowledge of the skilled person at the date of filing. 2.2 In order to determine whether a particular combination of insecticides acts synergistically, the patent at issue first determines the activities of the individual insecticides, the activity being the mortality rate, i.e. the percentage of dead insects, observed when a certain number of insects are exposed to a certain amount of insecticide over a certain period of time. From these individual activities, an expected activity for joint application of the two insecticides using the Colby equation is calculated. This expected potency value corresponds to a purely additive effect of the two insecticides. If the actual activity of the combination of the two insecticides is higher than this expected value, the insecticides work synergistically. If it is below this value, the insecticides of the combination act antagonistically. The application of this approach to assess the presence or absence of synergies between insecticides has not been contested between the parties. First, the Enlarged Board of Appeal was asked to confirm whether plausibility should be taken into account in the assessment of patentability, since there is no notion of “plausibility” in the rules and articles of the EPC.
“If you actually look at the words of the EPC, a purist would say that it puts the meaning of the words beyond the breaking point to draw plausibility from them – positively Humpty Dumpty-ish. For this reason, I assume that none of the legal justifications that remove the notion of plausibility from the definition of inventive step (obviousness) or sufficiency have much to do or even anything to do with the actual terms of the law. And the word plausibility itself is not in the law – in fact, it is never and never has been in any patent law. 13.6.1 In T 31/18 the underlying claim as filed concerned pharmaceutical tablets containing imatinib or pharmaceutically acceptable salts thereof. The claim at issue essentially concerned a tablet containing imatinib and cross-linked polyvinylpyrrolidone in certain quantities. With regard to the closest prior art, the patent proprietor formulated the problem essentially as the supply of imatinib tablets with a disintegration time of 20 minutes or less, and also presented experimental evidence to prove that this problem had been solved. According to one objector, this experimental evidence should not be taken into account since it concerned an effect whose effect had not been plausibly demonstrated with the tablets claimed in the application as filed. The board stated (reasons 2.5.2): The board decided that the patent had been found to be inventive and therefore valid if the subsequently published data could be taken into account, but that the patent lacked inventive step and would therefore not be valid if the subsequently published data could not be taken into account. Both parties agreed with the board that consideration should be given to whether the subsequently published data could be used to satisfy the plausibility requirement. A third line of case-law seems to reject the concept of plausibility altogether. This third line of case-law is hereinafter referred to as the application of the norm of lack of plausibility. The case-law applying that provision is hereinafter referred to as `lack of plausibility in the case-law`.
“Therefore, in the absence of evidence to the contrary in the common general knowledge for herbicide combinations containing herbicide (A), it cannot simply be assumed that a synergistic interaction would in itself be implausible for combinations not considered in the application as filed. This conclusion is consistent with decision T 863/12, in which the plausibility of an effect was confirmed, inter alia, by the fact that the general knowledge contained no evidence to call that plausibility into question … ” 10.1.2 D8 (claims 1 and 4) describes an agent containing a synergistically effective combination of compounds of formulas I and II-1. D8 (page 9, lines 5 to 6) also reveals that six specific compounds according to formula I are particularly preferred. These compounds comprise compound Ig, which is thiamethoxam within the meaning of claim 1 of the patent at issue. The board noted that three very different criteria were applied to determine whether or not subsequently published data could be taken into account in the assessment of inventive step. On the one hand, the “plausibilis ab initio” standard requires absolute disclosure of the data contained in the application as filed, demonstrating that the objective technical problem is solved by the claimed invention, while, on the other hand, the “no plausibility” standard allows the patent owner to rely on subsequently published data, independently of the data contained in the application as filed. The Commission noted that the standard of implausibility ab initio falls somewhere between these two extremes. 12.4.7 Therefore, taking into account the experimental data contained in the patent at issue and in the light of D23, the objective technical problem should be formulated less ambitiously.
Detailed information on the Committee`s reasoning for the referral and selection of individual issues is given below. In summary, however, the board considered that the earlier decisions fell into three distinct and incompatible categories, so that the correct approach was ambiguous. In addition, the board was unsure of the legal basis on which plausibility could be verified and whether the plausibility test was compatible with the EPO`s long-standing approach to problem solving. In its decision, the board also referred to a review article in which the author had stated that the word “plausibility” is not mentioned anywhere in the EPC. In my article “Where are your supporting data? Plausibility at the EPO”, I discussed the growing importance of “plausibility” at the European Patent Office (EPO), both in the context of inventive step and sufficiency, particularly in the life sciences. I also discussed how to reach the plausibility threshold even when data is missing. 12.4.4 The respondent submitted that, given the differences between D23 and the test examples in the patent at issue, the results of D23 did not affect the relevance of these test examples. The board disagrees with this argument. Assuming that the Enlarged Board of Appeal confirms that plausibility is required, it will consider the standard to be applied in assessing plausibility.
The EPO`s technical boards of appeal applied different approaches to assessing plausibility, which is why the Enlarged Board of Appeal had to adopt a uniform approach. The order for reference mentions two possible criteria for assessing plausibility: `plausible ab initio` and `implausibility ab initio`. “However, the board recalls in this respect that this case-law considers that the finding of plausibility is relevant to the examination of inventive step only if the present case permits doubts as to the ability of the claimed invention to solve the technical problem addressed and if it is so far removed from the claimed invention solving the problem formulated.” “The Board notes that the EPC does not require experimental evidence of patentability and considers that disclosure of the experimental data or results of the application as subsequently filed and/or published is not always necessary to demonstrate that the claimed subject-matter solves the objective technical problem.