invention, such as for a second medical use of a known substance where the "Swiss-type" claim might be required. Another reason to use a particular claim might be to catch a particular class of infringer. See also Catnic Components Ltd. v. Hill & Smith Ltd. (1982) Claim chart Clearance search and opinion Cloem, a company creating computer-generated variants of patent claims Disclaimer Doctrine of equivalents Probatio diabolica, in relation to product-by-process claims References Further reading The construction of product-by-process claims, 11th European Patent Judges' Symposium, Copenhagen, Official Journal of the EPO 2003, Special Edition, No. 2, p. 20-75 (pdf) External links European Patent Convention defining the extent of protection Protocol on the Interpretation of Article 69 EPC defining the role of claims (previously ) expressing the legal requirements regarding the form and content of the claims US patent law (Title 35 of the US Code) 35 USC § 101 patentable subject matter 35 USC § 112 specification and claims Studies on patent claims When small is beautiful: measuring the evolution and consequences of the voluminosity of patent applications at the EPO This paper addresses issues in measuring the voluminosity of patent applications (number of claims and pages) and highlights patterns in its evolution. Patent law