In the context of German patent law, the Formstein defence is a well-known defense against an alleged infringement by equivalents, wherein the alleged infringer claims that the embodiment alleged to be equivalent (to the subject-matter claimed in the patent) is not patentable and therefore the doctrine of equivalents does not apply.[1] It is similar to the UK's Gillette defense and the U.S. Wilson case.[2][3] The name "Formstein" means "molded kerbstone" and comes from a landmark decision of the Federal Court of Justice of Germany (Bundesgerichtshof) issued in 1986.[2][4][5]