Open Source Licensing: Software Freedom and Intellectual Property Law

Duration of Copyright and Patent

There is another fundamental difference between most forms of real and personal property and the intellectual property embodied in software. Real and personal property rights generally last forever, but copyrights and patents are temporary ownership rights that terminate with the passage of time.

In the United States, the Constitution mandates that such rights shall be granted “for limited times,” a particularly vague provision that allows Congress to define and change the terms of the copyright and patent monopolies, which it frequently does. Current U.S. law provides that, for new works, copyrights last for the life of the author plus 70 years or, for a work of corporate authorship, the shorter of 95 years from ...