Patent law has been formulated with an objective to promote and protect the inventions and methods. The object of granting a patent is to encourage and develop science, technology and industry.  A patent can be defined as a grant of exclusive rights to an inventor over his invention for a limited period of time. The exclusive rights conferred include the right to make, use, exercise, sell or distribute the invention in India. The term of a patent is twenty years, after the expiry of which, the invention would fall into the public domain.

In 1957, Govt. of India appointed Justice N. Rajagopala Ayyangar examine and review the Patent law in India who submitted his report September 1959 recommending the retention of Patent System despite shortcomings. The Patent Bill, 1965 based mainly on his recommendations incorporating a few changes, in particular relating to Patents for food, drug, medicines, was introduced in the lower house of Parliament on 21st September 1965. The bill was passed by the Parliament and the Patents Act 1970 came into force on 20th April 1972 along with Patent Rules 1972. This law was suited changed political situation and economic needs for providing impetus technological development by promoting inventive activities in the country.

Uruguay round of GATT negotiations paved the way for WTO. Therefore India was put under the contractual obligation to amend its patents act in compliance with the provisions of TRIPS. India had to meet the first set of requirements on 1- 1-1995. This was to give a pipeline protection till the country starts giving product patent. It came to force on 26th March 1999 retrospective from 1-1-1995. It lays down the provisions for filing of application for product patent in the field of drugs or medicines with effect from 01.01.1995 and grant of Exclusive Marketing Rights on those products.

India amended its Patents Act again in 2002 to meet with the second set of obligations (Term of Patent etc.), which had to be effected from 1-1-2000. This amendment, which provides for 20 years term for the patent, Reversal of burden of proof etc. came into force on 20th May 2003. The Third Amendment of the Patents Act 1970, by way of the Patents (Amendment) Ordinance 2004 came into force on 1st January, 2005 incorporating the provisions for granting product patent in all fields of Technology including chemicals, food, drugs & agrochemicals and this Ordinance is replaced by the Patents (Amendment) Act 2005 which is in force now having effect from 1-1-2005.