Re: Effect of transfer of copyright on free software licenses?

[Hyman Rosen]

Tim Smith wrote:
> Suppose I create a copyrighted work. I release it under a license such 
> as GPLv2. You use it, in a way that requires permission of the copyright 
> holder, but is in accord with GPLv2, so you are OK.
>
> Suppose now that I transfer the copyright to someone else.
>
> Do you now have something to worry about if the copyright assignee 
> wishes to stop you from copying, modifying, and distributing the 
> software?
>
> The GPL is meant to be a bare license, not a contract, but doesn't that 
> mean it provides no protection if the ownership of the work changes?

There is nothing to worry about. Courts will be presented with evidence
that it is standard industry practice to distribute software using unsigned
non-exclusive licenses, and with evidence that (in the case of the GPL) the
copyright holders intend that the license be irrevocable (as stated by the
license itself).

<http://caselaw.lp.findlaw.com/scripts/getcase.pl?court=fedclaim&vol=1999/97476c>
    Thus, nonexclusive licenses are explicitly removed from the 204(a)
    writing requirement.
    ...
    Under federal law, nonexclusive copyright licenses can be granted orally
    or implied from conduct.
    ...
    The existence of either an exclusive or nonexclusive license creates an
    affirmative defense to a claim of copyright infringement.