>>Copyright >> Principles BASIC PRINCIPLES FOR MANAGING INTELLECTUAL PROPERTY IN THE DIGITAL ENVIRONMENT PRINCIPLE 4 4. Copyright law should promote the maintenance of a robust public domain for intellectual properties as a necessary condition for maintaining our intellectual and cultural heritage.   The public domain is an intellectual commons that is the essential foundation for an informed and participatory society. It is critical for education, research, and the creation of new knowledge. With copyright terms extending for periods that can exceed 100 years (life of the author plus 50 years), the digital format in which a work is first fixed is likely to become obsolete long before the copyright expires. Security technologies used to protect copyrighted works from unauthorized use will exacerbate this danger if provision is not made for "unlocking" the work at the appropriate time. Information created by governments and public agencies, including under contract, should reside in the public domain as they do under current law. Privately created works that have passed a certain age should reside in the public domain as they do under current law. Copyright terms should expire on dates that are certain and easy to determine. Copyright law should assure that new technologies do not impede the passage of works into the public domain as contemplated by current law. Copyright law should facilitate preservation and migration to new media as technologies change. The educational community encourages a distinction between activities necessary for preservation and storage and activities to provide access to copyrighted works. Because technology evolves rapidly, the statutes and regulations governing preservation and storage should be flexible enough to apply to successive generations of technology.