I disagree that everyone else does this except distributions.

Companies apply their own patches to projects all the time (as an upstream maintainer I've been asked several times to help debug a patch that some company has used internally). Almost every company using Linux has patches on top of it that are for their specific project (all versions of Android have a forked Linux kernel). GitHub uses patched versions of Git (though one of their engineers is also incredibly prolific upstream). And so on.

The reason why people think distributions are the only ones doing it is because we maintain all of the software that is available for a full Linux system. So instead of only having patches for just one or two projects, we have patches for (probably) ~50% of packages in our distribution (most are bugfixes but there are plenty of not-just-bugfix examples). I think some folks just like to bash distributions because no matter what decisions we make we're going to piss someone off.

But again, we don't apply downstream patches because we like it. In fact downstream patches are an outright headache because we have to rebase them on version upgrades and so on.

Of course companies patch open-source software for their own use. But they either don’t distribute it, or they do so under a different trademark.

Just to focus on your own examples:

- Github patches Linux for their own private use. They do not distribute any Linux derivatives, and they don’t profit from the Linux trademark.

- Android does distribute a Linux derivative, and it is heavily patched, but it is distributed and marketed under the trademark “Android”. Google does not profit from the Linux trademark.

And that’s the difference. People don’t buy Android phones because they’re running Linux. But they buy Suse and Red Hat distributions specifically to get Linux.

So Suse and Red Hat are the only businesses which I know of, that are allowed to fork upstream software, modify it aggressively, and still profit from the upstream trademark.

The vast majority of free software projects do not have a registered trademark. In cases where a free software project does have a trademark, distributions usually will rename the package (distributions do have lawyers and they will usually kick up a fuss in cases like this).

The case of the Linux mark is really weird, because basically all distributions are given license to use it but almost everyone still specifies that the trademark is owned by Linus.

(Also my example for GitHub was their fork of git, not Linux.)

Didn’t you mention elsewhere in this thread that Suse and Red Hat patched Docker, not just to backport fixes but to add features which upstream explicitly didn’t want merged? Surely Docker has a registered trademark. So following your reasoning, Suse and Red Hat should have stopped using the Docker trademark. Yet they didn’t. That example seems to contradict your argument that distributions are very careful to respect registered trademarks, while considering unregistered trademarks to be basically a free-for-all.