Presenting Mathematical Concepts on the World Wide Web
Intellectual Property Rights ... and Wrongs

1. Many people use the term "public domain" incorrectly to describe material that is "available to the public."

2. Once a work is in the public domain, it cannot itself later be copyrighted.

3. For a basic work that is in the public domain, however, a subsequent author or entity can claim copyright to supplemental material published with it, or to the selection and organization of parts of the work.

4. Unless you are certain that intellectual property is in the public domain, it is safest to assume that it is covered by copyright. Do not rely on:
   • the absence of a copyright notice;
   • the fact that work is distributed for free;
   • the availability of a work in a public place (e.g., on the WWW).

Even if you find material that is freely available in a public place and contains no copyright notice, you cannot assume it is in the public domain. Ask for permission to copy, modify, adapt, or otherwise reuse it.

Note: On the Web, it is permissible to link to the original work of others without asking their permission first. Those folks made their work available so others could access it. On the other hand, it is wise to be courteous, and tell them if you plan to suddenly send huge numbers of folks their way, or otherwise link in such a way that may cause them any problems. IP Law comes into effect only if you copy their work and place it on your own site, disk, CD, etc.