ruby--ruby/lib/rubygems/LICENSE.txt

RubyGems is copyrighted free software by Chad Fowler, Rich Kilmer, Jim
Weirich and others.  You can redistribute it and/or modify it under
either the terms of the MIT license (see the file MIT.txt), or the
conditions below:

1. You may make and give away verbatim copies of the source form of the
   software without restriction, provided that you duplicate all of the
   original copyright notices and associated disclaimers.

2. You may modify your copy of the software in any way, provided that
   you do at least ONE of the following:

   a. place your modifications in the Public Domain or otherwise
      make them Freely Available, such as by posting said
      modifications to Usenet or an equivalent medium, or by allowing
      the author to include your modifications in the software.

   b. use the modified software only within your corporation or
      organization.

   c. give non-standard executables non-standard names, with
      instructions on where to get the original software distribution.

   d. make other distribution arrangements with the author.

3. You may distribute the software in object code or executable
   form, provided that you do at least ONE of the following:

   a. distribute the executables and library files of the software,
      together with instructions (in the manual page or equivalent)
      on where to get the original distribution.

   b. accompany the distribution with the machine-readable source of
      the software.

   c. give non-standard executables non-standard names, with
      instructions on where to get the original software distribution.

   d. make other distribution arrangements with the author.

4. You may modify and include the part of the software into any other
   software (possibly commercial).

5. The scripts and library files supplied as input to or produced as
   output from the software do not automatically fall under the
   copyright of the software, but belong to whomever generated them,
   and may be sold commercially, and may be aggregated with this
   software.

6. THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
   IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   PURPOSE.