Patents Issued in 1981 by Date
January
01/06/1981
01/13/1981
01/20/1981
01/27/1981
February
02/03/1981
02/10/1981
02/17/1981
02/24/1981
March
03/03/1981
03/10/1981
03/17/1981
03/24/1981
03/31/1981
April
04/07/1981
04/14/1981
04/21/1981
04/28/1981
May
05/05/1981
05/12/1981
05/19/1981
05/26/1981
June
06/02/1981
06/09/1981
06/16/1981
06/23/1981
06/30/1981
July
07/07/1981
07/14/1981
07/21/1981
07/28/1981
August
08/04/1981
08/11/1981
08/18/1981
08/25/1981
September
09/01/1981
09/08/1981
09/15/1981
09/22/1981
09/29/1981
October
10/06/1981
10/13/1981
10/20/1981
10/27/1981
November
11/03/1981
11/10/1981
11/17/1981
11/24/1981
December
12/01/1981
12/08/1981
12/15/1981
12/22/1981
12/29/1981
