Andreas Roehler writes:
Hmm, maybe could someone help me with an example?
I don't understand what example you want. Under U.S. law, it's
absolutely clear. If there is no license, all rights are reserved to
the rightsholder. Now, a license, like a contract, may be implicitly
or verbally granted, but if you don't have written evidence it's your
word against theirs, and the author will surely win in that case.
If there is an explicitly written license, but it's not GPLv3-
compatible, then you are out of luck. Again, there may be implicit or
verbal grant of permission to upgrade, but you would lose in court if
the rightsholder chose to withdraw it.
I really don't think it is *ethically* right to *assume* permission,
either. There are any number of people who have deliberately chosen,
for one reason or another, to license their code as GPLv2 (or even
GPLv1!) *only*. In any case where the permissions granted to us are
unclear, we should make serious efforts to determine who owns the code
or content, and get their permission.
If that turns out to be impossible (at least two of our significant
contributors have already left this vale of tears, for example), there
might be grounds for doing something unilateral. But the only thing
that protects our code from misuse is copyright law. It is
important that we respect it.
 According to many of our contributors; me, I'd be happier with a
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