T 0181/82 (Spiro compounds) of 28.02.1984

I. An effect which may be said to be unexpected can be regarded as an indication of inventive step; where comparative tests are sub submitted as evidence of this, there must be the closest possible structural approximation - in a comparable type of use - to the subject-matter of the invention.

II. Only known substances - not notionally described ones - qualify for use in comparisons of compounds. Such substances include those which are the inevitable result of the starting materials and the process applied thereto, even if one of the two reactants manifests itself as a chemical entity (C1 alkyl bromide) from a group of generically defined compounds (C1 - C4 alkyl bromides) (see "Diastereomers" T 12/81, OJ EPO 1982,296).