IFI

Patent Intelligence & Technology Report

Class Distribution for 1990-1999 

172 - EARTH WORKING (IPC A01B, E02F)

       1999  1998  1997  1996  1995  1994  1993  1992  1991  1990  Total

IOWA STATE UNIVERSITY RESEARCH FOUNDATION INC
          1     1     0     0     0     0     0     0     0     0      2
NEW HOLLAND NORTH AMERICA INC
          1     0     0     0     0     0     0     0     0     0      1
PORSCHE, DR ING H C F AG DE
          0     0     0     0     0     0     0     1     0     0      1
TOPCON K K JP
          0     1     0     0     0     0     0     0     0     0      1

Total     2     2     0     0     0     0     0     1     0     0      5