{% extends "base_compliance.html" %}
{% block subtitle %}Copyleft Compliance Projects - {% endblock %}
{% block submenuselection %}CopyleftPrinciples{% endblock %}
{% block content %}
[ <a href="/copyleft-compliance/principles.kr.html">한국어 판</a>]<br/>
[ <a href="/copyleft-compliance/principles.kr.html">한국어 판 (Korean)</a>]<br/>
<h1>The Principles of Community-Oriented GPL Enforcement</h1>
<p>The GNU General Public License (GPL) is the principal copyleft
license. Copyleft is a framework that permits ongoing sharing of a
published work, with clear permissions that <em>both</em> grant
<em>and</em> defend its users' freedoms — in contrast to other
free licenses that grant freedom but don't defend it.
Free software released under the GPL is fundamental
to modern technology, powering everything from laptops and desktops to
household appliances, cars, and mobile phones, to the foundations of
the Internet. Following the GPL's terms is easy — it gets more
complicated only when products distributed with GPL'd software also
include software distributed under terms that restrict users. Even in
these situations, many companies comply properly, but some companies
also try to bend or even break the GPL's rules to their perceived
advantage.</p>
<p>The Free Software Foundation (FSF) and Software Freedom Conservancy
(Conservancy) today lead worldwide efforts to ensure compliance with
the GPL family of licenses. The FSF began copyleft enforcement
in the 1980s, and Conservancy has enforced the GPL for many of
its member projects since its founding nearly a decade ago. Last
year, the FSF and Conservancy jointly
published <a href="https://copyleft.org/guide/"><cite>Copyleft and
the GNU General Public License: A Comprehensive Tutorial and
Guide</cite></a>, which includes sections such as
“<a href="https://copyleft.org/guide/comprehensive-gpl-guidepa2.html#x17-116000II">A
Practical Guide to GPL Compliance”</a> and
“<a href="https://copyleft.org/guide/comprehensive-gpl-guidepa3.html#x26-152000III">Case
Studies in GPL Enforcement</a>”, which explain the typical
process that both the FSF and Conservancy follow in their GPL
enforcement actions. (Shorter descriptions of these processes appear
in blog posts written
by <a href="https://www.fsf.org/blogs/licensing/compliance-situations">the
FSF</a>
and <a href="https://sfconservancy.org/blog/2012/feb/01/gpl-enforcement/">Conservancy</a>.)</p>
<p>As stalwarts of the community's freedom, we act as a proxy for users when
companies impede the rights to copy, share, modify, and/or
redistribute copylefted software. We require all redistributors to
follow the GPL's requirements in order to protect all the users' freedom,
and secondarily to support businesses that respect freedom
while discouraging and penalizing bad actors.</p>
<p>Copyleft is based on copyright; it uses the power of copyright to
defend users' freedom to modify and redistribute rather than to hinder
modification and redistribution. A traditional copyright license is