Michael Eager eager@eagercon.com
Sun Jul 15 20:11:00 GMT 2007

Richard Kenner wrote:
>> Richard> Now, suppose I apply it to the GPLv2 version of the file. One could
>> Richard> argue that such file is now GPLv3 and I think that'd be correct. 
>> Richard> But since the parts of the file being patched are identical, the
>> Richard> patch is indistinguishable from one that's derived from GPLv2 text.
>> Richard> This strikes me as a VERY murky legal areas.
>> I believe this scenario is exactly RMS's expectation if someone other
>> than the original author copies / backports a patch from a GPLv3 file.
> But I'm even worried about the case where the *original* author does it.
> So I developed a patch from a GPLv3 file.  I now go back and "develop" the
> same patch from the GPLv2 file, which has all relevant parts identical.
> The resulting patches are identical. Making the claim that these two
> identical things done by the same person in the same way have different
> copyright statuses might be legally correct, but as a practical matter
> seems absurd since there's no way to tell them apart as they're identical.
> This is a very bizarre situation!

Actually, the two patches don't have different copyright or licenses,
given your description.  It's really not possible to "un-know" the
original GPLv3 patch and create an identical GPLv2 from scratch.  The
second patch is clearly and directly derived from the first.

There might be a claim that someone else could develop the GPLv2
patch based on the GPLv2 sources, not looking at your patch or any
GPLv3 sources, in which case it would be either coincidence if they
happened to be identical, or a requirement of the context.

But this second patch is really irrelevant to the discussion at hand.

Michael Eager	 eager@eagercon.com
1960 Park Blvd., Palo Alto, CA 94306  650-325-8077

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