Term of a Patent

1The time period during which the patent shall have effect is known as the term of the patent. The term of every patent granted shall be for a period of 20 years from the date of filing of the application for patent. (Patents Act 1970, s 53(1).) The term of the patent in case of international applications filed under the PCT designating India shall be 20 years from the international filing date accorded under the PCT. Needless to say, a patent in force would come to a natural end at the expiry of the term of the patent.

2The 20-year term was introduced by the Patents (Amendment) Act 2002, prior to which patents were granted generally for a period of 14 years from the date of patent. Before the Patents (Amendment) Act 2002 came into force, the law provided for a shorter term for food and medicine or drug substances. Prior to the amendment, the term of patent for an invention claiming a method or process of manufacture of a substance, where the substance could be used as food or as medicine or drug was five years from the date of sealing of the patent or seven years form the date of the patent, whichever was shorter. Apart from ascribing a shorter period of protection for food and drugs, the Act in its original form also excluded patents for food and drug products.