In more recent decisions of the boards, any comparison with the prior art was found to be inappropriate for determining whether or not an invention was present.
In T 1173/97 (OJ 1999, 609) the board held that determining the technical contribution an invention achieves with respect to the prior art is more appropriate for the purpose of examining novelty and inventive step than for deciding on possible exclusion under Art. 52(2) and (3) EPC 1973. In T 931/95 (OJ 2001, 441) it was stated that there is no basis in the EPC for distinguishing between "new features" of an invention and features of that invention which are known from the prior art, when examining whether the invention concerned may be considered to be an invention within the meaning of Art. 52(1) EPC 1973. Thus there is no basis in the EPC for applying the so-called contribution approach for this purpose (see also T 258/03, OJ 2004, 575; T 1001/99, T 388/04 (OJ 2007, 16), T 619/02, OJ 2007, 63, T 553/02). By taking this position the board in T 1173/97 consciously abandoned the so-called "contribution approach" which had been applied, somewhat inconsistently, in the earlier case law. This was clearly a deliberate development of the case law. No decision of the boards of appeal has since challenged this choice by the board. It therefore stands as the established case law (G 3/08, OJ 2011, 10).