T 0012/81 - Novelty of chemical compounds - #32

Citation rank: 32
No. of citations: 121

T 12/81 is concerned with the concept of novelty of chemical compounds, more specifically with the different manners in which chemical compounds can be disclosed in the prior art. The decision has been referred to as "the leading decision on novelty of chemical compounds" (T 132/92, r. 4.3).

T 12/81 is being cited for holding two things:

Firstly: Disclosure in a cited document of the starting substance and the reaction process also discloses the end product (point 13 of the reasons).

And secondly: Selection from two lists establishes novelty (also point 13 of the reasons).

In the underlying examination case, the applicant claimed a specific diastereomer, namely the threo-form of 1-(4-chlorophenoxy)-1-(1-imidazolyl)-3,3-dimethyl-2-butanol, which is the product of a stereo-specific hydrogenation of 1-(4-chloro-phenoxy)-1-(imidazol-1-yl)-3,3-dimethylbutan-2-one.

The Examining Division refused the application for lack of novelty over German patent application DE-A 2 333 354, which disclosed five alternative hydrogenation processes, and a list of 20 possible starting materials, one of which was 1-(4-chloro-phenoxy)-1-(imidazol-1-yl)-3,3-dimethylbutan-2-one). The applicant appealed against the decision to refuse.

The Board, upon reviewing the appealed decision, firstly observed that the novelty requirement served the purpose of preventing that the state of the art is patented again. They remarked that there are different manners of claiming and disclosing chemical compounds. One manner is by describing the compound in terms of its chemical structure and/or formula. Another way is to define the compound through the process of its manufacture (product-by-process definition).

Regarding the question of novelty of the claimed compound over DE-A 2 333 354, the Board considered that a chemical entity, which is disclosed in a prior art document through its starting material and the process of manufacture, does form part of the state of the art:

"... the disclosure by description in a cited document of the starting substance as well as the reaction process is always prejudicial to novelty because those data unalterably establish the end product." (point 13 of the reasons)

In the case at hand, where the prior art document disclosed a list of 20 possible starting materials and 5 alternative hydrogenation processes, the applicant argued that two selections had to be made to arrive at the claimed compound, namely one selection from the list of 20 starting materials and a further selection from the five alternative processes. The applicant argued that the claimed compound was therefore new.

The Board did not agree. While it conceded that if, in order to obtain a claimed compound, two starting materials have to be selected from two lists of some length, then the substance resulting from the reaction of the specific pair from the two lists can be regarded as new. However, the Board found that the case at hand was different in that it only required selection of a single starting material from one list. The fact that also a hydrogenation process had to be selected from five alternative processes disclosed, in order to arrive at the claimed compound, was considered not to be comparable with the selection of a second starting material (point 14.3 of the reasons).

Hence, the claimed compound was regarded disclosed in the prior art document by disclosure of the specific starting material and the specific process yielding that compound, and the claims therefore lacked novelty.

The appeal was hence dismissed.

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Headnote:

1. In the case of one of a number of chemical substances described by its structural formula in a prior publication, that substance's particular stereospecific configuration (threo form) - though not explicitly mentioned - is anticipated if it proves to be the inevitable but undetected result of one of a number of processes adequately described in the prior publication by indication of the starting compound and the process. In such cases, novelty by selection cannot be claimed, since none of the possible combinations of all the listed starting compounds and process variants introduce a new element - indispensable for substance selection - that would result in a true and not just "identical" modification of the starting substances.

2. [...]

The full text of the decision can be accessed here.

Quotes from (10 random) decisions citing T 12/81 can be found here.