Interpreting the concept of equivalence

Rulings of the Italian Supreme Court on patentability of intermediate products and infringement by equivalence in the chemical field are infrequent. These two topics were brought under the spotlight in a decision by the court on December 2, 2016 in Industriale Chimica v Bayer Pharma.

Bayer Pharma owns the Italian portion of European patent EP918791, which claims a new process to produce drospirenone, an antiprogestinic drug used in hormone therapy. Bayer’s process is characterised by the synthesis of a stable intermediate product, called Idrox, which is subsequently catalytically oxidised to drospirenone by a ruthenium salt.

Industriale Chimica owns the Italian portion of European patent EP1828222, which claims a process to produce drospirenone in which the same intermediate Idrox is produced and catalytically oxidised to the end product, with the process making use of the organic compound Tempo as an oxidation catalyst instead of a ruthenium salt.

In its decision, the Italian Supreme Court confirmed the ruling of the Court of Appeal of Torino, which declared that the process of the ‘791 patent was infringed by equivalence by the process of ‘222. It held that claim 2 of the ‘791 patent, directed to the intermediate product, was invalid.

Infringement by equivalence

According to article 52 of the Italian Industrial Property Code, which implemented in the national law the Protocol of Interpretation of article 69 of the European Patent Convention (EPC), in determining the scope of protection conferred by the claims, due account shall be taken of any element which is equivalent to an element specified in the claims.

In its ruling, the Italian Supreme Court substantially confirmed the case law according to which infringement by equivalence must be assessed with regard to the inventive concept underlying the patented invention (the “heart of the patented invention”), which in the present case was identified by the court in the production of a stable intermediate—Idrox—from which the drospirenone can be derived.