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<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 &mdash; 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>

  ensure compliance with the GPL family of licenses. Conservancy has enforced

  the GPL for many of its member projects since its founding in 2006.  Conservancy also helped

  published, and hosts, <a href="https://copyleft.org/guide/"><cite>Copyleft and the GNU

  General Public License: A Comprehensive Tutorial and Guide</cite></a>

  (often called the “Copyleft Guide”),

  which includes sections such as

  &ldquo;<a href="https://copyleft.org/guide/comprehensive-gpl-guidepa2.html#x17-116000II">A

  Practical Guide to GPL Compliance&rdquo;</a> and

  &ldquo;<a href="https://copyleft.org/guide/comprehensive-gpl-guidepa3.html#x26-152000III">Case

  Studies in GPL Enforcement</a>&rdquo;.  Those sections explain the typical process

  that Conservancy follows in our GPL enforcement

  actions. (A Shorter descriptions of these processes appeared in <a href="https://sfconservancy.org/blog/2012/feb/01/gpl-enforcement/">earlier blog post</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

violated by giving the work to others without permission; a copyleft