Can a Mercurial fork change its license to AGPL?

[Matt Mackall]

On Sat, 2015-02-28 at 09:26 +0900, Kaz Nishimura wrote:
> I found a fork of Mercurial named Quicksilver <
> http://hg.quicksilver-vcs.org/quicksilver> is being licenced under the GNU
> AGPL.  Is it permitted to change a fork to the AGPL by the Mercurial
> copyright holder(s)?

Nope. Generally speaking you can't remove restrictions from a license..
or else copyright would be meaningless. The GPL says "we give you the
privilege to copy.. but you lose that if you try to restrict your
changes".

Sigh. I'll pass this on to the lawyers.

-- 
Mathematics is the supreme nostalgia of our time.