"Additional restrictions" can be funny. You may recall the FSF's position that the app store EULA placed "additional restrictions" on the GPL, a position that was and remains controversial.

In this case, it is a little harder to understand OpenBSD's interpretation of additional restrictions because they haven't listed their objections in any centralized place, but from reading around, they seem to believe:

* "You must cause any modified files to carry prominent notices stating that You changed the files" is an additional restriction * "any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of this License" is an additional restriction * The sheer length and complexity of the Apache license suggests to them there are other additional restrictions buried in there somewhere

> You may recall the FSF's position that the app store EULA placed "additional restrictions" on the GPL, a position that was and remains controversial.

I don't think that the position was contraversial, I just think that people took it the wrong way. The Apple EULA objectively has clauses in it that state that users must follow the "acceptable usage policy" and it is enforced regardless of any external agreements -- this would mean that Apple would be violating the GPL if they distribute any GPL software in their store.

You can add additional terms that permit distribution in the Apple store (as Signal has done), but the stock GPL does not permit distribution in the Apple store because the "acceptable use policy" is one of the things the GPL was made to fight against (the idea that users must act in an "acceptable" way to Apple when running software on their own computing devices).

> The Apple EULA objectively has clauses in it that state that users must follow the "acceptable usage policy" and it is enforced regardless of any external agreements -- this would mean that Apple would be violating the GPL if they distribute any GPL software in their store.

And Red Hat EULA objectively has clauses in it that you may not redistribute RHEL.

There is a slippery slope here, the FSF has decided for whatever reason that RHEL's restrictions "weren’t really restrictive, because they were so easy to comply with" [0] but there is really nothing "objective" about that determination.

[0] https://www.gnu.org/licenses/quick-guide-gplv3.html

You're being a tad disingenuous here. RHEL's EULA[1] is basically the same as SLE's, openSUSE's, Ubuntu's and so on. It only states that you are not allowed to use the RedHat trademarks when you redistribute RHEL -- and since RHEL (and the other distributions I mentioned) puts all of their trademarked components in a single "branding" package then it is not practically restrictive to make such a requirement. RHEL has no requirement that you cannot distribute some software (in fact, the distribution is under GPLv2 much like openSUSE and SLE).

Apple's EULA restricts users to only being able to use software they distribute under their "acceptable use policy". This is simply a violation of the GPL, with no wiggle room for discussion.

[1]: https://www.redhat.com/en/about/red-hat-end-user-license-agr...

The existing patent agreements are a contributor agreement, not part of the license. So, they restrict people from contributing, but don't actually provide any guaranteed protection for downstream users, as far as I can tell.

However, I'm not a lawyer and not involved, was just trying to summarize as well as I could, so I could be wrong.