I disagree with that, I don't see anything in the non-profit Eagle license that disallows giving away for free works produced with Eagle. The non-profit license simply doesn't allow commercial use, defined as making money. They even make a commercial exception for producing and using Gerber files for PCB production using the free version. http://www.cadsoftusa.com/freeware.htm
If somebody manufactures a product using the free version of Eagle for profit (other than simply generating gerber files) then they would be in violation of the license. If it's not for profit, then no problem.
No.
The GPL states that the creator gives permission for their work to be used commercially i.e. for profit which is incomparable with the terms of the free Eagle license which forbids commercial use.
I'm certainly no lawyer, just a guy who uses this stuff like the rest of you!
I'm not sure where the GPL came into this. I think you are confusing the license of the tool with the license of the work. The GPL does not require you to use free tools to create GPL-licensed works. The license of the tool and the license of the produced work are completely different things. You can use proprietary tools to create open source code or hardware, or open tools to create proprietary work. As for the GPL specifically, you can use whatever tools you want, including non-free, to create work licensed under the GPL.
http://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.html#NonFreeTools Your use of work
you create with
your freeware version of Eagle is required to be non-commercial by the Eagle license, the work itself can be under any license you wish, including the GPL. If somebody takes a copy of your work and wants to use it for a commercial purpose with Eagle,
their use of your work
in Eagle requires them to license Eagle appropriately. They can choose to not use Eagle and use something else, it has nothing to do with the license of your work, it has to do with their use of Eagle. If you grant them license to make money with your work they are completely free to do so regardless of what tools they choose to use. They simply, as always, need to comply with the licensing of those tools whether they be free or not.
If you create work with Eagle and license it under the GPL, you are granting rights to your work only, your licensing isn't requiring anybody to use Eagle or any particular tool. If somebody wants to use your GPL-licensed work, it's entirely up to them if they want to use it in a commercial manner and to use any tools they choose and comply with the licensing of those tools as appropriate.
Examples of similar issues:
You can use GPL toolchains to produce proprietary code. (Use a GNU compiler to compile a commercial proprietary library or other binary.)
You can use proprietary tools to produce open work. (Use Microsoft Word to create and distribute an open document.)
The Linux kernel code itself was maintained in a non-open source management system. (Bitkeeper 2002-2005. And yes, it was controversial.)
If I'm wrong and there is any conflict between the GPL and Eagle licensing, I see it being on Eagle's side, not the GPL. However, Eagle's description of their freeware limitations is pretty straightforward to me, it doesn't intend at all to restrict licensing or distribution of work created with Eagle. Rather, it just requires that if you are going to work with Eagle for commercial use (even with some exceptions!) you need to buy a registration. I don't see that as conflicting at all with open source or open hardware, since it doesn't place any restrictions on how you license your work, it only requires
your use to be non-commercial. It doesn't restrict any anybody else's use of your work to be non-commercial, they can buy a registration for Eagle or choose to use another tool.