The Mercurial license is GPLv2

[Dave Dribin]

On Aug 4, 2008, at 11:38 AM, Matt Mackall wrote:
> Typically relicensing is done by finding all past contributors and
> asking them if the new license is acceptable. And I already know one
> person who would object before asking anyone. I for one am not a fan  
> of
> the BSD license. I would be very disappointed to see a company like
> Apple come along, pick up Mercurial, make a bunch of shiny  
> improvements,
> then force me to pay for it if I wanted a copy.

At the same time, GPL blocks out some legitimate usages for Mercurial  
that would actually be beneficial to Mercurial.  Mercurial won't see  
any commercial GUI front-ends or adoption into closed-source IDEs, for  
example.  One benefit of Subversion over any of the leading DVCs is  
its more liberal license [1].  This has resulted in a much wider  
adoption of Subversion than Mercurial can ever achieve.  On the  
pragmatic/practical side, Apple has very little incentive to modify  
Mercurial as they'd want it to be compatible with the "official" open  
source version.

Perhaps a middle ground where the Mercurial back-end library is LGPL  
would satisfy both camps.  This would require any changes to the  
library to be contributed back, but still allow closed-source/ 
commercial usage.

-Dave

[1]: http://subversion.tigris.org/license-1.html