The Patent Prior User Rights Act and the Patent Reexamination Reform Act : hearing before the Subcommittee on Patents, Copyrights, and Trademarks of the Committee on the Judiciary, United States Senate, One Hundred Third Congress, second session on S. 2272, to amend chapter 28 of Title 35, United States Code, to provide a defense to patent infringement based on prior use by certain persons, and for other purposes and S. 2341, to amend chapter 30 of Title 35, United States Code, to afford third parties an opportunity for greater participation in reexamination proceedings before the United States Patent and Trademark Office, and for other purposes, August 9, 1994.