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A form of licensing that encourages the distribution of software at no charge for noncommercial uses.

[After copyright.]

cop′y·left′ed (-lĕf′tĭd) adj.


(Law) law a form of licensing that imposes fewer restrictions on the use of a work than copyright


A distribution agreement that allows everybody who receives a copy of the work in question to freely distribute or adapt it on the condition that they do not claim copyright on it for themselves.
References in periodicals archive ?
The law surrounding OSS agreements and copyleft is still evolving, Kunick says.
One reason why these communities continue to provide free solutions without legal protection is the social enforcement of the sharing ethic that copyleft enforces with legal right.
The GNU General Public License was the first popular copyleft license, and it still dominates licensing of "copylefted" software.
As explained by the Free Software Foundation (FSF), which claims ownership of the phrase "copyleft" and one of the most widely used licenses, the GNU General Public License (GPL), copyleft is "designed to make sure that you have the freedom to distribute copies of free software, that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things.
GPLs are an example of "copyleft"--a licensing scheme which, says Wikipedia, can give every person who receives a copy of a work permission to reproduce, adapt or distribute it: as long as any resulting copies or adaptations are also bound by the same copyleft licensing program.
Chapter 4 distinguishes the public and private sectors while Chapter 5 offers alternatives, including the Creative Commons and copyleft movement (see COMMUNICATION RESEARCH TRENDS, Vol.
Such a license might be termed a flexible copyright, or meta license, that incorporates features of both proprietary copyright and open source copyleft.
Copyleft generally requires that if open source software is incorporated into proprietary source code, the entire source code (open source + proprietary) must be made available to others on the same terms as the existing public license.
21) Copyleft is a play on the word copyright and is the practice of using copyright law to remove restrictions on distributing copies and modified versions of a work for others and requiring that the same freedoms be preserved in modified versions (GNU Operating System, What is Copyleft?
Unlike GPLv3, the AGPLv3 license enforces copyleft when software is distributed as a service (SaaS), which is a fundamental requirement when considering how consumers and enterprises purchase and use software today.