- Limitations on Copyrights
Idea v. Expression Distinction
law may protect the tangible product of a mind's work, the idea
or factual basis underlying this work can not be copyrighted.
For example, "news"
may not be copyrighted, only the particular way of expressing
Pure factual compilations,
such as phone books, often do not receive copyright protection.
By analogy, a collection of bare hyperlinks directing World
Wide Web users to related material might not be copyright material.
Finally, when there
are significantly limited means of expressing an idea or fact,
such as E=mc2, the expression may be used without infringing
on a copyright holder's rights. 
protection extends for only a set time period. After a copyright
expires, the author's ownership rights are transferred to
the general public.
use" is a legally permissible use of a copyrighted work,
even if the use would otherwise
interfere with the author's
Unprotected by Copyright. Available at <<http://www.bitlaw.com/copyright/unprotected.html>>
Last accessed, December 1, 2002. See also, Bruce P. Keller,
Internet and Online Law, in Fourth Annual Internet Law Institute,
Vol. 1, 169, 179-180 § 6.02.