Can you alter the MIT license?

[Bruce Perens]

From: Jules Bean <jmlb2 at hermes.cam.ac.uk>
> Even public domain isn't your copyright [um.. unless you wrote it, of
> course].

You're a bit confused about public domain. Please read this entire message
carefully.

Placing a work in the public domain is not the same as granting broad
rights to that work. If you place on your work the notice "I place
this work in the public domain", you abandon your copyright rights
entirely. You literally no longer have a copyright on that work at
all. That is different than saying "Copyright 1999 Bruce Perens, Do
anything you want as long as you preserve my copyright notice." For example,
someone can create a derived work of public-domain material and copyright it,
and can place any license terms they wish on it, and need not attribute the
work to you!

Claiming for a business advantage, to be the author of a public-domain work
may be fraud. That's criminal law, however, not copyright law. Copyright
law does not require you to put proper author attribution on public-domain
work.

> Copyrights can be explicitly assigned to others, bought and sold as
> commodities.  But they can't be given up entirely...

OK, you dared me.

	I abandon my copyright rights on this message and place it in the
	public domain. Bruce Perens, 15-November-1999.

It's entirely my right to do that.

> 'Public domain', literally, applies to something upon which there is no
> copyright at all.  This would be something which has no attributable
> author, or more likely a long-dead author (copyright thus expired).

Or the copyright owner has intentionaly placed the work in the public domain.

> In particular, the GPL says that you must make available the source of the
> whole work.  Now this is an additional restriction on top the the MIT one,
> but it's not in conflict with the MIT one - it doesn't ask you to do
> anything you aren't allowed to do.

Right.

> Current popular interpretation is that you can't, if your software is
> 'BSD-with-advertising-clause'.  If you don't have the adv-clause, or
> you're happy to give it up, then you can GPL parts of your software, and
> include other peoples GPL'ed software.  But you must satisfy the terms of
> the GPL (which you are not likely to find a problem).

Note also that you can issue _any_number_of_licenses_ on software as long
as you own its copyright. Want to put the same work under GPL, BSD, X11,
Artistic, MPL, and so on? Do all at once. Producers of derived works and users
get to pick a license, they can't mix and match terms from more than one.

	Thanks

	Bruce