Sure you can sell it, and under whatever terms you like. But you have to _also_ provide the full source under the GPL, not under "the GPL with additional constraints".

I'm no lawyer, but I highly doubt it'll hold. And buying Linux from them could be very toxic as "GPL violation" => "termination of license" -- and I'm not sure how you go about getting a new license :)

No, under the GPL you have the right to redistribute the source. You don't have a right to receive new patches or maintain any particular subscription, that is a different consideration that you can maintain in a separate contract.

True,

But punishing people for exercising their rights, is quite similar to placing restrictions on said rights.

I'm no lawyer, but you generally can't out-smart the law :)

Of course you can be punished for exercising your rights. There is no better example than free speech: you're free to say whatever you want, and your customers are free to leave in response. The considerations of many contracts include some form of restricting your rights in return for something.

IANAL either, in case that wasn't obvious.

That depends on how you read section 6 of the GPL2. It states in part:

> You may not impose any further restrictions on the recipients' exercise of the rights granted herein.

The central right granted under the GPL is, of course, the right to modify and redistribute the source. I'm not a lawyer, and I'm certain that Grsecurity could find a number of legal arguments that what they're doing is allowed (likely starting with the claim that terminating a relationship with a customer isn't legally imposing a restriction on that customer's actions), but the idea that they're in violation of the GPL isn't pulled from thin air.

It is enough for them to send the source on a written request. May be a link (working!), may be source code on a disk.

Someone will have to set up an automatic snail mailer.

If they do not respect that, they are explicitly violating GPL.

The point is if they punish you (such as discontinue business relationship) because you send a request to obtain the source, and exercise the rights you've been granted in the GPL, well, that's an additional restriction.

I'm no lawyer, but the spirit of the law or a contract matters. You can't avoid a speeding ticket because the wheels of your car wasn't touching the road in the photo :)