Invalidity and Amendment of Granted Patents

Abstract This chapter focuses on the law governing the validity and amendment of patents in the UK and US. The grant of a patent does not guarantee its validity. The chance that a patent will be held to be valid if challenged depends on the completeness of the search performed; the strictness of examination of the patent in the patent office; the legal and technical competence of the patent examiner; the chance of intervention by third parties during the patent office proceedings; and the pro- or anti-patent attitude of the national courts. Patents granted by the European Patent Office (EPO), Japanese Patent Office, or US Patent and Trademark Office are subject to a relatively rigorous substantive examination. However, patents in other countries, such as South Africa, Belgium, or even the Netherlands, are granted after a formal examination, without any investigation as to whether the claimed invention meets the patentability criteria.