Selection invention

A selection invention consists in choosing, within a larger set already disclosed, a particular element or subset which displays properties the prior art did not foreshadow. It is frequent in chemistry and pharmaceuticals: selection of a compound within a family defined by a general formula, of a sub-range within a numerical range, of a particular salt or crystalline form. The selection invention raises a question of novelty as much as of inventive step.

The novelty of the selection invention

First, the generic disclosure of a family of compounds does not, in principle, destroy the novelty of a particular compound not individually described in it. Second, for the selection of a sub-range within a known numerical range, the European Patent Office requires that the sub-range be narrow and sufficiently removed from the concrete examples of the prior art. Third, a list of expressly named compounds destroys the novelty of each of them. A choice from two lists of sufficient length may, by contrast, be new. The examination guidelines are available on the website of the European Patent Office.

The inventive step of the selection invention

Novelty is not enough. A selection invention involves an inventive step only if the selection produces an unexpected or surprising technical effect in the light of the earlier teaching, or if it solves a problem the prior art did not allow to be solved. A mere arbitrary choice among equivalent possibilities, or routine optimisation, is not patentable. The demonstration of the effect rests on comparative trials, whose plausibility must emerge from the original application.

Key points

In practice, the selection invention is a tool for prolonging the protection of a technology and a favourite battleground of pharmaceutical litigation, where it is often challenged as evergreening. Its validity depends on the quality of the experimental data and the drafting of the claims. The firm argues these questions before the Paris Judicial Court and the UPC, as presented on the page pharmaceutical patents and regulation.