Once you've licensed something as open-source and published, that version with that license will always be there. You could take a future private version of the thing (assuming no code contributions) and license that differently.
If you have copyright.
(Now if there is a Free version under a contracted-for rather than gratuitous license, that's a bit more secure, though there are ways that could go away, too.)
Real question. I am not a lawyer, but would assume arbitrary revocation would essentially be a breach of contract. (But I guess it's not technically a contract since it's one sided?)
The law governing licenses (of all kinds.)
> If you grant rights to someone, in what legal way can you simply revoke those rights?
If the grant is gratuitous (not contracted for) you generally have no legal obligation not to simply revoke those rights (it is exactly the same case as inviting someone into your house and then ejecting them when you decide they've worn out their welcome, which is also a case of gratuitous license.)
> Real question. I am not a lawyer, but would assume arbitrary revocation would essentially be a breach of contract.
Right, if there was a contract, then revocation inconsistent with its terms would generally be a breach, which would still least present a cause of action for damages and may permit an equitable remedy extending the license.
Most F/OSS license scenarios are not contract licenses, and even when they are, publication with an offer of a license isn't a contract, the offer must be accepted without the offer having expired or having been revoked first for a contract to exist.
If I agree that my neighbor can have 5 feet on my side of the property line in perpetuity and put the offer in writing, I can simply change my mind later and take it back?
But if you instead gave your neighbor that 5 feet then you would not be able to revoke it.
A key part of most open source licenses is that the author is not giving up ownership of the code. This is why many projects require a copyright reassignments for contributions to avoid being hamstrung by an author revoking their right to use that contribution sometime in the future.
This is explicit in GPLv3: "All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met."
There's also a legal theory that the GPL is, or can be depending on the circumstance of a particulsr case, a contract license rather than a gratuitous license [0], but even in that case the contract offer would be revocable, and the GPL itself only irrevocable with respect to licensees with whom a contract was formed prior to the offer being revoked (because FOSS licenses are sublicensable, that licensee could offer sublicenses to the original work, but might not, e.g., if they chose not to do any of the acts which required such an offer.)
[0] which may not actually save the day, either, since some courts have held that contract licenses are revocable, but that revocation in violation of the terms of the contract makes available damaged for breach of contract rather than compulsory extension of the license.
I'm not sure why concern would be raised with respect to the original contract offer. It seems entirely irrelevant given that any participant has full rights under the contract terms.
Given the way Linux is copyrighted (with many holders), it'd be an absurd situation if any copyright holder could just decide, after the fact, that they don't want their code being distributed under that license anymore. In fact...I think that's been litigated in SCO vs. IBM. So...what are you basing your legal theory on here?
Even leaving aside general issued on the revocability of licenses that aren't special to copyright law, the US has a special provision making all licenses and transfers of rights by authors under copyright revocable by written notice, during a 5 year window 35 years from when they occurred; see 17 USC Sec. 203.
> So...what are you basing your legal theory on here?
The general American (Anglo-American, I think, as I'm fairly certain the principle is a common law one which is older than the US) of licenses.
Further, revocation of copyright on works with multiple authors must be signed off on by a majority of copyright holders, per the law you've cited. That's literally impossible with something like Linux (but maybe not with something like Arduino, if it only has a tiny number of authors, I don't know).
If it's so simple and obvious, why has it never happened in 30+ years of GPL software, when billions of dollars are at stake?
"The general American (Anglo-American, I think, as I'm fairly certain the principle is a common law one which is older than the US) of licenses."
Many things in "common law" have been replaced by written legislation and case law. Modern copyright bears no resemblance, and only has only tenuous connections, to common law. Copyright is among the most debated and litigated categories of law in the modern world, with legislation, legal precedent, and even international treaties covering it. If your position is that it is as you say because common law is as you say, that just sounds really shaky. Now, I need to ask you to back up the assertion that "common law" is the law in force on copyright in any developed Western nation, because that seems to be the crux of your interpretation of the law.
I don't know, man. I'm not an expert, by any means, but I'm just not following your reasoning here, at all.
My understanding of the GPL is that it is a one way street for released code. New releases can be under a new license if all of the authors agree to it, but once something is out there under the GPL, it is always under the GPL. Nothing you've said makes me think otherwise because the weight of precedent seems to disagree with you.
Wow, that's rather incredible. It's enheartening to see a US copyright law that seems biased toward authors rather than publishers.
The provisions of section 203 safeguard[] authors against unremunerative transfers. A provision of this sort is needed because of the unequal bargaining position of authors, resulting in part from the impossibility of determining a work’s value until it has been exploited.
http://www.sfwa.org/2013/08/second-bite-apple-termination-ri...
However, the widespread assumption is certainly that it doesn't require a contributor license agreement to keep this whole open source thing from crashing down. Which it would if an arbitrary developer could threaten pulling out their code from some project N years later. In today's climate, it's pretty reasonable to assume that if no one has pulled that sort of blackmail, no one thinks it has legs.
As far as i'm aware, legally, giving attribution attribution in exchange for a thing has been held to be plenty consideration since nearly the dawn of time.
(Even giving up the right to sue for warranty claims would likely be sufficient consideration, but no open source license explicitly says that, they just disclaim there are warranties, which is not quite the same)
There are some that are significantly more problematic. WTFPL is a good example of a maybe-gratuitous license.
Common ones have clear consideration (agreements to do certain things with your patent rights for downstream users, etc).
I have not yet found anyone who believes you would have a strong argument that most open source licenses are gratuitous.
Agreement to do a thing you didn't have to do (give attribution, include a copy of a license, whatever) in exchange for something, is plenty consideration.