Patents last 20 years from filing date — this is standard worldwide under the TRIPS Agreement. After 20 years, the invention enters the public domain. Copyright lasts author's lifetime + 60 years (much longer).

1. 1 Pick up Patents Act, 1970.
2. 2 Go to Section 53(1).
3. 3 Read: 'the term of every patent granted shall be twenty years from the date of filing.'

The text reads: Section 53(1): Every patent shall be for a term of twenty years from the date of filing of the application.