Patents Reinstated Due to the Acceptance of a
                       Late Maintenance Fee From 5/16/97


Patent           Serial            Filing          Issue           Granted
Number           Number            Date            Date            Date

Re. 34,693       08/049,887        04/20/93        08/09/94        05/21/97
Re. 34,849       08/151,948        11/15/93        02/07/95        05/16/97
4,468,650        06/431,590        09/30/82        08/28/84        05/20/97
4,474,711        06/443,132        11/19/82        10/02/84        05/20/97
4,483,396        06/507,567        06/24/83        11/20/84        05/19/97
4,561,097        06/658,571        10/09/84        12/24/85        05/21/97
4,653,670        06/866,793        05/23/86        03/31/87        05/22/97
4,653,880        06/707,231        03/01/85        03/31/87        05/19/97
4,669,273        06/860,633        05/07/86        06/02/87        05/20/97
4,697,241        06/707,040        03/01/85        09/29/87        05/22/97
4,722,689        06/811,103        12/20/85        02/02/88        05/16/97
4,740,107        07/083,935        08/05/87        04/26/88        05/19/97
4,781,180        06/909,899        09/22/86        11/01/88        05/19/97
4,788,962        07/104,294        10/05/87        12/06/88        05/20/97
4,805,134        06/817,389        01/09/86        02/14/89        05/19/97
4,925,423        07/112,515        10/26/87        05/15/90        05/21/97
4,998,848        07/329,183        03/27/89        03/12/91        05/21/97
5,004,275        07/364,628        07/13/89        04/02/91        05/20/97
5,035,230        07/484,227        02/23/90        07/30/91        05/20/97
5,089,786        07/540,498        06/19/90        02/18/92        05/20/97
5,100,051        07/646,098        01/25/91        03/31/92        05/22/97
5,117,140        07/699,091        05/13/91        05/26/92        05/19/97
5,118,397        07/593,028        10/05/90        06/02/92        05/20/97
5,131,684        07/782,634        10/25/91        07/21/92        05/20/97
5,135,298        07/581,544        09/12/90        08/04/92        05/16/97
5,140,251        07/571,773        08/22/90        08/18/92        05/19/97
5,148,116        07/754,714        09/04/91        09/15/92        15/16/97
5,155,902        07/736,792        07/29/91        10/20/92        05/21/97
5,157,121        07/731,460        07/17/91        10/20/92        05/22/97
5,157,905        07/692,554        04/29/91        10/27/92        05/21/97
5,161,378        07/682,699        04/09/91        11/10/92        05/19/97
5,166,565        07/490,631        05/21/90        11/24/92        05/19/97
5,177,011        07/637,990        01/03/91        01/05/93        05/20/97
5,184,934        07/727,868        07/10/91        02/09/93        05/21/97