The ANTLR recognizer generator tool was written by (with many contributions) 

     Prof. Terence Parr at USF

The C runtime and related C code generation elements were written by

    Jim Idle (jimi idle ws s/ /./g) with no contributions at all because
                                    nobody else was crazy enough to do it.

The C runtime and the ANLTR tool itself are distributed under the BSD license
which basically gives the right to so anythign with it, so long as you
recognize the authors. See here:

 [The "BSD licence"]
 Copyright (c) 2005-2009 Jim Idle, Temporal Wave LLC
 http://www.temporal-wave.com
 http://www.linkedin.com/in/jimidle

 All rights reserved.

 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions
 are met:
 1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.
 2. Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.
 3. The name of the author may not be used to endorse or promote products
    derived from this software without specific prior written permission.

 THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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 NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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 THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.