The original copyright notice of MOPAC6:
Notice of Public Domain nature of MOPAC

'This computer program is a work of the United States
Government and as such is not subject to protection by
copyright (17 U.S.C. # 105.) Any person who fraudulently
places a copyright notice or does any other act contrary
to the provisions of 17 U.S. Code 506(c) shall be subject
to the penalties provided therein. This notice shall not
be altered or removed from this software and is to be on
all reproductions.'
