On Wed, 14 Jul 2021, Warner Losh wrote:
The X10R3 license sure looks like a standard MIT
license. The other license
statements that were included also read very much like open source, or
at least a strong intention of being open source, absent any drafting flaws.
Copyright 1985 by the Massachusetts Institute of Technology
Permission to use, copy, modify, and distribute this
software and its documentation for any purpose and without
fee is hereby granted, provided that the above copyright
notice appear in all copies and that both that copyright
notice and this permission notice appear in supporting
documentation, and that the name of M.I.T. not be used in
advertising or publicity pertaining to distribution of the
software without specific, written prior permission.
M.I.T. makes no representations about the suitability of
this software for any purpose. It is provided "as is"
without express or implied warranty.
This software is not subject to any license of the American
Telephone and Telegraph Company or of the Regents of the
University of California.
Ironically...that's closer to a "3-clause BSD" license.
-uso.