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---
Generator: 'texi2html 1.82'
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title: Untitled Document
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1. Why Upgrade to GPLv3 {#why-upgrade-to-gplv3 .chapter}
=======================
@firstcopyingnotice{{ Copyright © 2007, 2009 Richard Stallman\
{This essay was originally published on <http://gnu.org>, in 2007. This
version is part of @fsfsthreecite} Version 3 of the GNU General Public
License (GNU GPL) has been released, enabling free software packages to
upgrade from GPL version 2. This article explains why upgrading the
license is important.
First of all, it is important to note that upgrading is a choice. GPL
version 2 will remain a valid license, and no disaster will happen if
some programs remain under GPLv2 while others advance to GPLv3. These
two licenses are incompatible, but that isn’t a fundamental problem.
When we say that GPLv2 and GPLv3 are incompatible, it means there is no
legal way to combine code under GPLv2 with code under GPLv3 in a single
program. This is because both GPLv2 and GPLv3 are copyleft licenses:
each of them says, “If you include code under this license in a larger
program, the larger program must be under this license too.” There is no
way to make them compatible. We could add a GPLv2-compatibility clause
to GPLv3, but it wouldn’t do the job, because GPLv2 would need a similar
clause.
Fortunately, license incompatibility matters only when you want to link,
merge or combine code from two different programs into a single program.
There is no problem in having GPLv3-covered and GPLv2-covered programs
side by side in an operating system. For instance, the TeX license and
the Apache license are incompatible with GPLv2, but that doesn’t stop us
from running TeX and Apache in the same system with Linux, Bash and GCC.
This is because they are all separate programs. Likewise, if Bash and
GCC move to GPLv3, while Linux remains under GPLv2, there is no
conflict.
Keeping a program under GPLv2 won’t create problems. The reason to
migrate is because of the existing problems that GPLv3 will address.
One major danger that GPLv3 will block is tivoization. Tivoization means
certain “appliances” (which have computers inside) contain GPL-covered
software that you can’t effectively change, because the appliance shuts
down if it detects modified software. The usual motive for tivoization
is that the software has features the manufacturer knows people will
want to change, and aims to stop people from changing them. The
manufacturers of these computers take advantage of the freedom that free
software provides, but they don’t let you do likewise.
Some argue that competition between appliances in a free market should
suffice to keep nasty features to a low level. Perhaps competition alone
would avoid arbitrary, pointless misfeatures like “Must shut down
between 1pm and 5pm every Tuesday,” but even so, a choice of masters
isn’t freedom. Freedom means *you* control what your software does, not
merely that you can beg or threaten someone else who decides for you.
In the crucial area of Digital Restrictions Management (DRM)—nasty
features designed to restrict your use of the data in your
computer—competition is no help, because relevant competition is
forbidden. Under the Digital Millennium Copyright Act and similar laws,
it is illegal, in the US and many other countries, to distribute DVD
players unless they restrict the user according to the official rules of
the DVD conspiracy (its web site is <http://www.dvdcca.org/>, but the
rules do not seem to be published there). The public can’t reject DRM by
buying non-DRM players because none are available. No matter how many
products you can choose from, they all have equivalent digital
handcuffs.
GPLv3 ensures you are free to remove the handcuffs. It doesn’t forbid
DRM, or any kind of feature. It places no limits on the substantive
functionality you can add to a program, or remove from it. Rather, it
makes sure that you are just as free to remove nasty features as the
distributor of your copy was to add them. Tivoization is the way they
deny you that freedom; to protect your freedom, GPLv3 forbids
tivoization.
The ban on tivoization applies to any product whose use by consumers is
to be expected, even occasionally. GPLv3 tolerates tivoization only for
products that are almost exclusively meant for businesses and
organizations.
Another threat that GPLv3 resists is that of patent deals like the
Novell-Microsoft pact. Microsoft wants to use its thousands of patents
to make users pay Microsoft for the privilege of running GNU/Linux, and
made this pact to try to achieve that. The deal offers rather limited
protection from Microsoft patents to Novell’s customers.
Microsoft made a few mistakes in the Novell-Microsoft deal, and GPLv3 is
designed to turn them against Microsoft, extending that limited patent
protection to the whole community. In order to take advantage of this
protection, programs need to use GPLv3.
Microsoft’s lawyers are not stupid, and next time they may manage to
avoid those mistakes. GPLv3 therefore says they don’t get a “next time.”
Releasing a program under GPL version 3 protects it from Microsoft’s
future attempts to make redistributors collect Microsoft royalties from
the program’s users.
GPLv3 also provides users with explicit patent protection from the
program’s contributors and redistributors. With GPLv2, users rely on an
implicit patent license to make sure that the company which provided
them a copy won’t sue them, or the people they redistribute copies to,
for patent infringement.
The explicit patent license in GPLv3 does not go as far as we might have
liked. Ideally, we would make everyone who redistributes GPL-covered
code give up all software patents, along with everyone who does not
redistribute GPL-covered code, because there should be no software
patents. Software patents are a vicious and absurd system that puts all
software developers in danger of being sued by companies they have never
heard of, as well as by all the megacorporations in the field. Large
programs typically combine thousands of ideas, so it is no surprise if
they implement ideas covered by hundreds of patents. Megacorporations
collect thousands of patents, and use those patents to bully smaller
developers. Patents already obstruct free software development.
The only way to make software development safe is to abolish software
patents, and we aim to achieve this some day. But we cannot do this
through a software license. Any program, free or not, can be killed by a
software patent in the hands of an unrelated party, and the program’s
license cannot prevent that. Only court decisions or changes in patent
law can make software development safe from patents. If we tried to do
this with GPLv3, it would fail.
Therefore, GPLv3 seeks to limit and channel the danger. In particular,
we have tried to save free software from a fate worse than death: to be
made effectively proprietary, through patents. The explicit patent
license of GPLv3 makes sure companies that use the GPL to give users the
four freedoms cannot turn around and use their patents to tell some
users, “That doesn’t include you.” It also stops them from colluding
with other patent holders to do this.
Further advantages of GPLv3 include better internationalization, gentler
termination, support for BitTorrent, and compatibility with the Apache
license. All in all, plenty of reason to upgrade.
Change is unlikely to cease once GPLv3 is released. If new threats to
users’ freedom develop, we will have to develop GPL version 4. It is
important to make sure that programs will have no trouble upgrading to
GPLv4 if and when we write one.
One way to do this is to release a program under “GPL version 3 or any
later version.” Another way is for all the contributors to a program to
state a proxy who can decide on upgrading to future GPL versions. The
third way is for all the contributors to assign copyright to one
designated copyright holder, who will be in a position to upgrade the
license version. One way or another, programs should provide this
flexibility for future GPL versions.
------------------------------------------------------------------------
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