All of the code for the STIPPLE compilers, debuggers, linkers, run-time library and so forth are covered by the following copyright:
Copyright (c) 199x by Wayne C. Gramlich. All rights reserved.
Permission to use, copy, modify, distribute, and sell this software for any purpose is hereby granted without fee provided that the above copyright notice and this permission are retained. The author makes no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty.
This is basically the same copyright notice used for the code in the X11 release. Basically all it says is that you are free to use the code and you do not owe me a dime; likewise if you do not like the code for any reason, I do not owe you a dime. That is all there is to it.
The extracted documentation and source files are availabe.