x3270 Lineage

Here is the official copyright notice for x3270 3.2:
Modifications Copyright © 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001 by Paul Mattes.
Original X11 Port Copyright © 1990 by Jeff Sparkes.
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.

Copyright © 1989 by Georgia Tech Research Corporation, Atlanta, GA 30332.
All Rights Reserved. GTRC hereby grants public use of this software. Derivative works based on this software must incorporate this copyright notice.

The Georgia Tech fonts (the fonts with the name "gt" in them), carry an additional notice:
Copyright © 1990 by the Georgia Institute of Technology.
All rights reserved except for those rights explicitly mentioned below.
Permission is granted to distribute freely or to modify and distribute freely any materials and information contained herein as long as the above copyright and all terms associated with it remain intact.
The 3270-20 font is derived from an NCD font, so it carries an additional notice:
Copyright © 1989-1991 Network Computing Devices, Inc.
NCD is a registered trademark of Network Computing Devices, Inc.

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 NCD may not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. NCD makes no representations about the suitability of this software for any purpose. It is provided ``as is'' without express or implied warranty.

NCD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL NCD BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

The ComplexMenu sources are derived from the MIT X11R5 Athena SimpleMenu widget, and carry an additional notice:
Copyright © 1989 Massachusetts Institute of Technology

Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted without fee, 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.

M.I.T. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL M.I.T. BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

The 5250 emulation code carries one more copyright:
5250 Emulation Code Copyright © Minolta (Schweiz) AG, Beat Rubischon.
What this means is that you (whomever you may be) may use x3270 3.2 for whatever purpose you desire, and the only restriction is that you include the above notices in each copy or derivative work you distribute.

x3270 3.2 comes from several sources: 

                                   3270tool
                                      |
                                      V
                                   x3270 1.2
                                      |
              +-----------------------+------------------------+
              |                       |                        |
              V                       V                        V
 x3270 1.2-cutpaste-iso8859-1     x3270 2.65               x3270 3.1
                                                               |
                                                               V
                                                           x3270 3.2
                                                               |
                                                               V
                                                         [you are here]
The original work was 3270tool, a 3270 emulator for Suntools (Sun's original proprietary windowing environment). This was developed by Robert Viduya at Georgia Tech, and is why GTRC's copyright notice is first.

3270tool was then ported to X11R4 by Jeff Sparkes, and given the name "x3270." This is why his name is second.

x3270 3.1 started with Jeff's x3270 version 1.2, and was made very much bigger by Paul Mattes, with contributions and suggestions by a number of users from the net. x3270 3.2 is a major revision to the x3270 code, and is the version you are looking at right now.

Given the spirit of creativity on the net (and the availability of source code) there are a number of other versions of x3270, all based on Jeff's code, most notably v1.2-cutpaste-iso8859-1 and v2.65. x3270 3.1/3.2 is a separate line of development from these other versions. Patches for those versions do not apply to x3270 3.2, and some of the features found in those versions may not be in 3.2. X resource definitions are generally not compatible, either.