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Copyright: Choosing How To Share

Guide introduces the fundamental concepts of copyright and provides resources to comply with and exercise it.

Creative Commons Licenses

Creative Commons Logo

  • "Reasonable, flexible copyright" to allow sharing, reuse and remix legally
  • Licenses to communicate permitted uses for creative and scholarly works
  • Creative Commons' four variables
  1. Attribution - Give credit to the creator.
  2. Noncommercial - Cannot charge others based on your use of the work.
  3. No Derivative Works - Can only use the material in its entirety.
  4. Share Alike - must include the same license with your version of the work.

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Public Domain

Works fall under the public domain through:

  • expiration of copyright: the copyright has expired.
  • failure to renew copyright: the owner failed to follow copyright renewal rules.
  • dedication: the owner deliberately places it in the public domain.
  • no copyright protection available: copyright law does not protect this type of work.

Table for Determining Public Domain Status

Works published in the U.S. before 1928 In the public domain
Works published in the U.S. after 1928 through 1963 Initial term of 28 years. If not renewed during the 28th year, the work falls into the public domain
Works published in the U.S. after 1927 but before March 1, 1989 Generally, if a work is published without copyright notice under the authorization of the copyright owner and the law does not provide an exception for the omission, the work is in the public domain

(c) 2005-2009 The Board of Trustees of the Leland Stanford Junior University. With the exception of the Nolo Copyright and Fair Use Overview, this work is licensed under a Creative Commons Attribution-Noncommercial 3.0 United States License.

Copyleft

Copyleft is a concept that developed in the computer software community and led to the GNU public license.

Copyleft is a general method for making a program (or other work) free, and requiring all modified and extended versions of the program to be free as well.

  • It is found in the source code of some freely available software.