Subject: Re: Can you alter the MIT license?
From: (Bruce Perens)
Date: Mon, 15 Nov 1999 12:24:23 -0800 (PST)

From: "Scott Johnston" <>
> Can you give an example of a term you can *add* to a non-copyleft free
> software license that would not conflict with the freedoms originally
> granted?

Look at all of those commercial X servers: Sun, SGI, HP, XI Graphics, etc.
They are not free software, yet they are based on software under the X11
license. Look at the commercial BSD OS derivatives, especially the ones on

The X11 license grants freedom to redistribute, but does not mandate that
derived works grant freedom to redistribute too, and it does not require
that you redistribute source code. The GPL is one of only a few licenses that
requires that derived works be freely redistributable.

A number of licenses pass the OSD that do not require that freedom be passed
on ad infinitum.