MS-PL/GPL compatibility, was Re: For Approval: Microsoft Permissive License

Alexander Terekhov alexander.terekhov at
Thu Aug 23 20:29:41 UTC 2007

On 8/23/07, Wilson, Andrew <andrew.wilson at> wrote:
> Alexander Terekhov wrote:
> >On 8/23/07, Wilson, Andrew <andrew.wilson at> wrote:
> >[...]
> >> Alexander, the case under discussion here is what license
> >> applies to a derivative work which includes source code
> >> licensed under MS-PL combined with source code
> >> under a copyleft license to create a derivative work.
> >
> > What the heck do you mean by combining?
> Let's try cut-and-paste to keep it simple.  Can I cut and paste
> a non-trivial amount of EPL code (let's say 10 lines or more)

Would you real want to steal only 10 lines of BSD code? :-)

> into a BSD-licensed module?  I think the consensus answer is
> yes, and EPL follows and applies to the resulting derivative.

Mere cut-and-paste without modification of code would constitute
either compilation, collective work, or noncopyrightable aggregation,
and neither affect copyright owners' adaptation rights (vs
reproduction rights if copied portion deemed protected) under Section
106 of the U.S. Copyright Act.

It won't be a "BSD-licensed module" though. EPL portion will remain
under the EPL and BSD portion will remain under the BSD. It isn't
rocket science.

> Can I paste a non-trivial section of code licensed under MS-PL
> into a module licensed under EPL?

See above.

> Don't think so, for the reasons originally outlined.
> > In the case you really want to
> > take this or that interesting element from any licensed code and use
> > it as basis for your modification of other licensed code (vs
> > aggregating multiple computer program works without doing any
> > modifications), I have yet to see how such an element could survive
> > the AFC test filtering (hint: it must be something really interesting)
> So it is your position that all copyleft licenses are unenforceable?

Given your use of GNUish term "copyleft" to cover not only GNUish
silliness, that isn't my position.


"Along those lines FSF created a special terminology (often called
"GNU-speak") that redefines the meaning of existing words like  "free
software" (FSF provides a definition of the term), and introduces a
new word "copyleft" (also with the definition). Some pages demonstrate
a real artistry in playing with the term "copyleft": "real copyleft"
(GPL),  "strong copyleft" (GPL),  "not a strong copyleft" (whatever)
"non-copyleft" (a bad thing) and such pearls as "simple, permissive
non-copyleft free software license"  or "a free software license,
partially copyleft but not really" [FSF1999b]. "

                                                          -- Bezroukov

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