There's a common misconception that licensing conditions can establish pretty much whatever a rightsholder might wish, but that is an incorrect generalization based on a misunderstanding of how and why copyleft and the GPL works.

Holding exclusive rights to copy, adapt, distribute, publish and publicly perform a work of authorship enables the rightsholder to authorize (i.e., license) the exercise of these rights in limited forms (e.g., you, the licensee, are allowed to make up to N copies; you are allowed to remove [but not to add or translate or replace]; you are allowed to distribute but only on Thurday mornings; ...), and even in conditioned forms (you are allowed to publish modified copies as long as they link back to the original), and combinations thereof (you are allowed to publicly perform, but only on weekends, and provided that all marketing materials name the authors and link to their website).

But note that running a program, or reading a book privately, or listening to a song, or watching a movie are not among the exclusive rights. This means that a license that states "you can only run this program on Mondays", or a book that states "you are not allowed to read this outside the European Union", or "you must obtain a license before you're allowed to listen to this", etc, is not a license, it's more likely just a false statement written by someone who holds this common misconception, and its effects are dubious at best. There is no leverage to impose or enforce such claims, because there's no exclusive right over these actions to begin with: the person can already take them, unconstrained, even without a license. It would take something other than a copyright license, such as a contract, with prior and explicit acceptance, for the other party to give up the non-exclusive right they inherently had.

Another set of rights that are not exclusive under copyright are those to make hardware out of a hardware design. A license that attempted to limit or condition these activities would be about just as effective as any version of the GPL at it, i.e., not at all.

That is very much unlike a common analogy that people attempt to apply, by which copyrights held on source code apply to object code built out of it. Copyright law holds (IIUC, IANAL, YMMV) that it's the same work. But this is not the case for hardware built out of a hardware design: the design is subject to copyright, but the hardware isn't.

So it's not just that this is out of scope of software freedom, it's also out of scope of copyright licensing. There is no such thing as GPL-licensed hardware, because copyright does not apply to hardware, so there's no exclusive right that the GPL licenses there.

Now, one could think the way to go would be to set out to push for legislation that enabled freedom-respecting hardware designers to get something along the lines of copyleft. That might seem desirable, but I find that position naïve. While copyleft has worked, to some extent, as a defense for us, it mostly only reduces the amount of damage that copyright brings upon us all. That's not a desirable state of affairs, it's more like making a lemonade out of very bitter lemons that were handed to us.

Expanding copyright to cover hardware built out of copyrighted designs, so that we could use copyleft on it, might enable us to make a little more lemonade, but it would also get us tons of dry bitter lemons that we wouldn't be allowed to turn into lemonade or anything else. It would be more of a setback than progress.

Putting it another way: if copyright didn't apply to software right now, would you want to impose on everyone all of the social costs and abusive potential of copyright on software just so that we could have copyleft? I'd rather not.

So blong,

  • 2023-10-03 UPDATE: Disambiguated in response to this report by Alexandre Hannud Abdo.

  • 2023-10-03 UPDATE: Fixed typo on 2023-10-03, thanks Adriano Rafael Gomes for the report on IRC.