Evergreening

Evergreening refers to the strategy by which the holder of a pharmaceutical patent seeks to prolong the commercial exclusivity of a medicine beyond the expiry of the initial patent. The term comes from English and literally means keeping evergreen. It has no legal definition, but it structures a significant part of pharmaceutical litigation.

Evergreening techniques

Evergreening rests on the filing of so-called secondary patents around an active ingredient whose basic patent is approaching expiry. These patents cover a new crystalline form, a salt, an enantiomer, a formulation, a dosage, a manufacturing process or a new therapeutic indication. Each of these titles, if valid, may delay the entry of a generic. The supplementary protection certificate and the paediatric extension sometimes complete the strategy, but they stem from a distinct legal mechanism.

The limits set by patent law

Patent law does not prohibit patenting an improvement. It requires, however, that each secondary patent meet the conditions of novelty, inventive step and sufficiency of description. A generic company attacking a secondary patent most often argues that the claimed form or dosage followed obviously from the prior art, or that the alleged technical effect is not plausible. The nullity action and the non-infringement defence are the ordinary instruments of that challenge.

The limits set by competition law

Competition law may sanction the abusive use of the strategy. The Court of Justice of the European Union has accepted that an abuse of dominant position may result from misleading representations made to patent offices, and agreements delaying the entry of generics, known as pay-for-delay agreements, are scrutinised severely by the European Commission and by national authorities.

The firm acts in disputes between originators and generic companies, on the validity of secondary patents, provisional measures and launches at risk. See our page pharmaceutical patents and the resources of the European Patent Office.