[SGVLUG] An interesting (I hope) GPL question

David Lawyer dave at lafn.org
Tue Apr 18 01:13:41 PDT 2006


Just type "man gpl" to view the license.  At least this works in
Debian.
On Mon, Apr 17, 2006 at 02:28:29PM -0700, Emerson, Tom wrote:
> 
> Let's take this a step further: Mr. A decides to sell the program as
> well [yeah, he's entitled to do this...] and in fact /sells/ a copy
> to Mr. C, however, Mr. C doesn't request a copy of the source.  Mr.
> C, in turn, gives in to Mr. B's whining and gives him a free copy.
> At this point, could *you* be compelled to give the source to Mr. B
No.
> (or ANYONE who /claims/ he received a copy from Mr. C?)  Again, I
> think not -- in this case because he chose to redistribute the
> binary, Mr. C is /responsible/ for distributing the source, not the
> author nor Mr. A (i.e., C's "upline").  The fact that Mr. C
> neglected to get a copy of the code is his fault, and his recourse
> would be to request a copy from Mr. A.

Correct.  C was in violation of the gpl since he failed to make
available the source to B.  So if the license is violated, then the
code B has comes under copyright law (as if there was no license) so B
isn't allowed to even run the binary, let alone get source code.

As a practical matter, courts would likely apply common law and common
sense to this case.  C only gave away one copy wrongfully.  C would be
warned not to do this again.  And C would need to make restitution by
getting the source from A and passing it along to B.  Did C harm B by
not having the source code available?  Possibly yes since B is not supposed to
run the binary.  But who will sue B for running the binary?  B could
have legally gotten the binary if source had been supplied too, so A
hasn't been harmed by B running the binary.  So I suspect that if
agreements are inadvertently violated but no harm is done, there is no
basis for damages.  

The purpose of the gpl requiring that the source be available is so
that one can study and possibly modify the code.  So if B had given
away thousands of copies without being able to supply source, he might
have done some harm if people had wanted source. 

Is B allowed to run the code?  Technically not.  But C needs to inform
B of this.  But that wouldn't be necessary if C gets source from A and
passes it on to B.
			David Lawyer


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