Assignments
A patentee may assign the whole or any part of the patent rights to the whole of India or any part thereof. There are three kinds of assignments: legal assignment, equitable assignment and mortgages. An assignment of an existing patent is a legal assignment where the assignee may enter his name as the patent owner. A certain share given to another person is called an equitable assignment and a mortgage is when patent rights are wholly or partly transferred to obtain money.
Licenses
A patentee may, by a license, permit others to make, use, or exercise, the invention which otherwise would not be allowed. The license should be in writing and the terms of which must be given in the application filed with the Controller. A license maybe given in express terms or implied from the circumstances. An exclusive license excludes all other persons including the patentee from the use of invention In a limited license the limitation may arise as to persons, time, place, manufacture, use or sale.
Compulsory Licenses and Government use of inventions
Under certain circumstances like when reasonable requirements are not satisfied, a very high royalty is quoted, when a patent cannot work without another related patent or on notification by the Central government, the Controller can grant a license to an interested person.
The Central or State government can use for a purpose of its own all patented inventions or processes either with or without royalty.
 Revocation of a patent
A patent may be revoked by various modes namely revocation in the public interest by the Government or relating to atomic energy by Controller. A patent may also be revoked for non-working. The High Court may revoke a patent on noncompliance with the requirements for use of an invention or on petition by a person interested on various specified grounds.
A patentee may at any time offer to surrender his patent by giving notice to the Controller, whom after hearing the parties may revoke the patent.
