T 0014/83 - Non-working embodiments not necessarily mean insufficient disclosure - #89

Rank: 89
No. of citations: 59

T 14/83 is concerned with sufficiency of disclosure. It is often cited for its ruling that sufficiency of disclosure is not to be judged on the basis of the claims alone, but that the description and drawings need to be taken into account. For example, T 291/89 cites T 14/83 as follows:

"As regards sufficiency of disclosure the Board wishes to point out that this question has to be judged not merely on the basis of claims but also on the basis of the description: cf. decision T 14/83, OJ EPO 1984, 105."

In more specific cases, T 14/83 is cited for saying that it is not necessarily detrimental to sufficiency of disclosure, if some of the examples given in a patent/application fail, although these examples are carried within parameter ranges defined in the claim in question. Occasional failure is not detrimental, if it takes e.g. only takes some additional experiments to convert failure to success, as long as these experiments do not involve inventive step. For example, T 583/93 states (in the original language):

"Wie in T 14/83 (ABl. EPA 1984, 105) festgestellt wurde, beeinträchtigt das gelegentliche Mißlingen eines beanspruchten Verfahrens nicht dessen Ausführbarkeit im Sinne des Artikels 83 EPÜ, wenn es z. B. nur einiger Versuche bedarf, um den Fehlschlag in einen Erfolg zu verwandeln; diese Versuche müssen sich allerdings in vertretbaren Grenzen halten und dürfen keine erfinderische Tätigkeit erfordern (Entscheidungsgründe Nr. 6, 1. Absatz)."

In the case underlying T 14/83, the claim at issue related to a polymerisation process in which a monomer is polymerised with a multifunctional co-monomer, wherein the resulting prolymer product has a "gel content" of 10-80% and a "polymerisation degree" of greater than 1000. The claim also defined ranges for two process parameters, namely the reaction temperature (0-50°C) and the "amount of polyfunctional co-monomer" (0.01-10%).

From various examples in the description it followed that even if the temperature and the "amount of the polyfuctional co-monomer" were held in the claimed ranges, the resulting product did not in all cases fulfill the claimed product requirements in terms of "gel content" and "polymerisation degree". The examination division, in the contested decision, was of the opinion that this resulted in a lack of sufficiency (Art. 83 EPC).

The Board, however, found that one should not judge claim 1 solely on the basis of its own wording, but one should take the content of the entire application into account (see above). In particular, the Board found that Tables 1 and 2 (which contained process parameters and resulting product properties) should have been taken into account. After making a very detailed analysis  of the numbers given in Tables 1 and 2, the Board concluded that the skilled person could deduce certain rules, which rules would then allow the skilled person to purposefully modify process parameters so as to convert failure to success, i.e., make products having the claimed properties.

Specifically, the Board in T 14/83 states in the Reasons:

"7. The resins obtained in runs 8, 13 and 14 present too low a gel content. The practical rules set out above offer the expert two correcting measures therefor: (i) increase of the amount of the polyfunctional comonomer as the result of which the polymerization degree of the "soluble fraction" declines, or (ii) decrease of the polymerization temperature whereby the "polymerization degree" goes up. According to what is wanted the polymerization degree can be simultaneously affected in contrary directions. The matter is similar in the runs No. 17 and 18 where the soluble fraction of the resin has too low an average polymerization degree. To redress this undesired result two possibilities also exist: (iii) diminishing the amount of the polyfunctional comonomer whereby the gel content declines consequentially, or (iv) decreasing the temperarature, which entails a consequential increase of the gel content. Finally, run 12 shows that the resin presents too high a gel content and too low an average polymerization degree of the soluble fraction. In that case only one remedy can be applied to correct the result. Operating as set out in case (iii) above will diminish the gel content and simultaneously increase the polymerization degree. In conclusion, it is clear that the expert who carried out the claimed processes strictly in accordance with the instructions and occasionally missed the desired target at the first attempt would be able to bring about the desired composition of the resin quickly and reliably by having recourse to the said empirical rules disclosed in the description of the present specification."

Based on this analysis, the Board concluded that the skilled person had sufficient guidance to successfully perform the invention, and that the claimed polymerisation method was thus sufficiently disclosed.

By way of a comment, it seems to me that T 14/83 puts a limit on a different concept developed by Appeal Boards, namely the "over-the-whole-area-claimed" concept, according to which sufficiency of disclosure is only present, if the invention can be performed over the whole area claimed (Case Law Book II.C.4.4). This concept, however, has always been in conflict with a further concept developed by the Boards, namely the concept of (at least) "one way of carrying out the invention" being sufficient to fulfill the requirement of Art. 83 EPC (CLB II.C.4.2). (I must confess that I never really understood when which of the two concepts is to be applied.)

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Headnotes:

1. The question whether an invention has been disclosed sufficiently clearly and completely is not to be decided solely on the basis of the content of the claims. If a chemical invention involves the task of manufacturing a product with certain measurable properties (e.g. gel content or degree of polymerisation of a copolymer), and this task is performed by means of a process involving several variables, then the means of its performance are to be regarded as sufficiently disclosed within the meaning of Article 83 EPC if, encountering occasional lack of success notwithstanding strict adherence to the prescribed limits of those variables, clear information, contained in the description, regarding the effects of individual variables on the properties of the product enables the person skilled in the art to bring about the desired properties quickly and reliably in such an event.
2. If teaching thus disclosed cannot be defined in a claim precisely enough to rule out occasional failure, such a claim is not to be objected to, provided it is possible to deduce from the description the action to be taken - which also cannot be precisely defined - by way of fine tuning of the variables.

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