Copyleft is the legal technique of granting certain freedoms over copies of copyrighted works with the requirement that the same rights be preserved in derivative works. In this sense, freedoms refers to the use of the work for any purpose, and the ability to modify, copy, share, and redistribute the work, with or without a fee.

2022年1月2日 · Copyleft is a general method for making a program (or other work) free (in the sense of freedom, not “zero price”), and requiring all modified and extended versions of the program to be free as well. The simplest way to make a program free software is to put it in the public domain, uncopyrighted.

2016年8月12日 · Copyleft is not a separate legal framework from copyright; copyleft exists within the rules of copyright. So what is copyright? The exact definition varies based on jurisdiction, but the essence is this: the author of a work has a limited monopoly on the copying (hence the term "copyright"), performance, etc. of the work.

Copyleft is a form of licensing: it is not just another name for public domain. However, in a copyleft license, when a person gives or sells a work (changed or not changed) to a friend, the person must allow the friend to do the things which the author of the original work has allowed in the license to the person.

2024年8月9日 · In the case of Free and Open Source Software (FOSS), copyright and copyleft are two concepts that mainly determine how the software can be utilized, altered, and disseminated. Copyright offers the authors legal rights to regulate the distribution and utilization of …

Copyleft, license granting general permission to copy and reproduce intellectual property. Where copyright protects society’s interests in invention and creativity by providing individual incentives through copyright control, copyleft protects social interests in knowledge creation by vesting

2025年3月19日 · Copyleft, a play on the word "copyright," is the practice of offering users of a work the right to freely distribute and modify the original work, but only under the condition that the derivative works be licensed with the same rights.

2021年3月3日 · This guide provides an overview of copyleft, the various types of copyleft licenses, and how to use copyleft to license a creative work.

The copyright holders grant the freedom to copy, modify, convey, adapt, and/or redistribute this work (except Appendices B – E) under the terms of the Creative Commons Attribution Share Alike 4.0 International License. A copy of that license is available at https://creativecommons.org/licenses/by-_sa/4.0/legalcode.

The Blue Oak Guide to Copyleft. This short guide gives a brief introduction to copyleft licenses, an important kind of open software license. Understanding copyleft licenses at a high level unlocks a world of new software, from Linux to WordPress to LibreOffice and more. Permissive and Copyleft. Experts distinguish two kinds of open software ...