Editor's note: last week's article on
GPL attacks drew some questions on just why the GPL cannot be enforced like
a contract. We're pleased to announce that we have convinced Pamela Jones
to expand on that issue for us.
There has been considerable FUD of late asserting that, if a company
inadvertently incorporates GPL code into its proprietary code, it can
be forced to release its proprietary code under the GPL. This isn't
new FUD. It's old FUD, but it is coming from some new sources. Even some attorneys have been saying this in the media and at
various conferences. While it's not a crime to misunderstand the GPL,
and it certainly isn't rare, it does arouse unnecessary fears about whether
the GPL is safe to use or work with. Is it true? Can you lose your code
this way? No, and the reason why hinges on
the GPL being a license and not a contract.
A lot of the confusion about the GPL stems from this central issue:
Is the GPL a license or a contract? The reason this issue matters is
that contracts are enforced under contract law, which is done
state by state, and there are certain necessary elements to qualify as a
valid contract. Licenses, instead, are enforced under copyright
law at the federal level. The penalties available are not the
Let's analyze and see how this all relates to the recent FUD. First of
all, what is a license? A license is just a
permission to do something you otherwise wouldn't be allowed to do. When
I want to go fishing, for example, I have to get a fishing license from
the local municipality. That's a license, as its name implies. But
why? Why isn't it a contract? Because there are no further agreed-upon
promises, no reciprocal obligations. It would be a contract if I said
to the owner of a pond: if you give me a license to fish in this pond,
I'll give you half of all the fish I catch. In that scenario, each of
us has voluntarily entered into a kind of promise. We each give the
other something of value, so if I get the license and then I don't give
over half of all my catch of the day, the pond owner can sue me for not
living up to the terms of the contract.
Eben Moglen, the Free Software Foundation's attorney, who is primarily
responsible for enforcing
the GPL, explains the difference between contracts and licenses like
The word 'license' has, and has had for hundreds of years, a
specific technical meaning in the law of property. A license is a
unilateral permission to use someone else's property. The
traditional example given in the first-year law school Property
course is an invitation to come to dinner at my house. If, when
you cross my threshold, I sue you for trespass, you plead my
'license,' that is, my unilateral permission to enter on and use my
A contract, on the other hand, is an exchange of obligations,
either of promises for promises or of promises of future
performance for present performance or payment. The idea that
'licenses' to use patents or copyrights must be contracts is an
artifact of twentieth-century practice, in which licensors offered
an exchange of promises with users: 'We will give you a copy of
our copyrighted work,' in essence, 'if you pay us and promise to
enter into certain obligations concerning the work.' With respect
to software, those obligations by users include promises not to
decompile or reverse-engineer the software, and not to transfer the
Very clear, but what about
First, the name tells you what the
authors intended: General Public License. It doesn't say
"General Public Contract" or even "General Public License Contract". So
they intended it to be a license, not a contract. Does it fit the
definition? Professor Moglen:
The GPL, however, is a true copyright license: a unilateral
permission, in which no obligations are reciprocally required by
the licensor. Copyright holders of computer programs are given, by
the Copyright Act, exclusive right to copy, modify and redistribute
their programs. The GPL, reduced to its essence, says: 'You may
copy, modify and redistribute this software, whether modified or
unmodified, freely. But if you redistribute it, in modified or
unmodified form, your permission extends only to distribution under
the terms of this license. If you violate the terms of this
license, all permission is withdrawn.'
Suppose a company really did mingle GPL code into
a program with its own proprietary code and then distributed the
merged product under a proprietary license or without living up to the
terms of the GPL? Now what happens? What will the judge do now?
Order the code released under the GPL over the wishes of the owner?
Stop and think. What happens if you violate the terms of a fishing
license? For example, the license may restrict how much fish you can
catch on a particular day or what kinds of fish you can keep, what
sizes, etc. Suppose you violate the terms of the license. What
happens? You lose your license to fish. There may be a fine to pay.
That's essentially the same thing that happens under the GPL,
except it's nicer, because the company gets to choose what it wishes to
do under the terms of the GPL. If it still isn't resolved, and it goes
to a judge, however, it's enforced as a violation of copyright law, not
contract law. Here is Professor Moglen's explanation of what happens:
Because the GPL does not require any promises in return from
licensees, it does not need contract enforcement in order to work.
A GPL licensor doesn't say in the event of trouble "But, judge, the
licensee promised me he wouldn't do what he's doing now." The
licensor plaintiff says 'Judge, the defendant is redistributing my
copyrighted work without permission.' The defendant can then
either agree that he has no permission, in which case he loses, or
assert that his permission is the GPL, in which case he must show
that he is obeying its terms. A defendant cannot simultaneously
assert that the GPL is valid permission for his distribution and
also assert that it is not a valid copyright license, which is why
defendants do not 'challenge' the GPL.
The claim that a GPL violation could lead to the forcing open of
proprietary code that has wrongfully included GPL'd components is
simply wrong. There is no provision in the Copyright Act to
require distribution of infringing work on altered terms. What
copyright plaintiffs are entitled to, under the Act, are damages,
injunctions to prevent infringing distribution, and--where
appropriate--attorneys' fees. A defendant found to have wrongfully
included GPL'd code in its own proprietary work can be mulcted in
damages for the distribution that has already occurred, and
prevented from distributing its product further. That's a
sufficient disincentive to make wrongful use of GPL'd program code.
And it is all that the Copyright Act permits.
So when you read claims that the GPL is perhaps not
enforceable because you don't sign it or click on a form, or because of
a lack of privity, or because there is a lack of consideration, or some
such, you'll know that the person misunderstood the GPL and thought in
terms of contract law. It's a common error. They don't shoot you at
dawn for not fully understanding the GPL. But at the same time, it's
good to know that the problems people think they see in the GPL
generally are the result of not understanding it, not from any weakness
in the GPL itself.
Similarly, when you hear that the
GPL is viral and can force proprietary code to become GPL, which a
couple of lawyers have been saying, you'll know that isn't true. If
you steal GPL code, you can expect an enforcement action.
But this action can only be enforcement of a license, not a contract, and
a forced release under the GPL can't be imposed on you under copyright
law. It's not one of the choices, as Professor Moglen has explained.
You do have a choice under the GPL: you can stop using the
stolen code and write your own, or you can decide you'd rather release
under the GPL. But the choice is yours. If you say "I choose neither,"
the court can impose an injunction to stop you from further
distribution, but it won't order your code released under the GPL. Your
code remains yours, as you can see, even in a worst case scenario.
Of course, you could avoid all such troubles in the first place by
not stealing GPL code to begin with. But if something happens
inadvertently and some rogue employee sneaks some GPL code into your
proprietary product, the sky isn't falling. It's a manageable risk and a
solvable problem. No one wants to steal your code in retaliation or
force it to be something you don't want it to be. The GPL is
unequivocally a license, and that's the truth.
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