In a number of chemistry decisions the problem and solution approach – based on landmark decisions T 1/80 (OJ 1981, 206), T 24/81 (OJ 1983, 133) and T 248/85 (OJ 1986, 261) – involves the following steps:

a) establishing the closest prior art;

b) defining the problem in the light of that prior art;

c) identifying the solution;

d) demonstrating the success of the solution;

e) optionally reformulating the problem;

f) examining the obviousness of the solution in view of the state of the art.

Demonstrating the success of the solution and reformulating the problem are particularly important steps (see T 231/97, T 355/97).