DIFF Subgroup
G11B 3/08503 Full Title
Recording by mechanical cutting, deforming or pressing, e.g. of grooves or pits; Reproducing by mechanical sensing; Record carriers therefor (G11B11/00, take precedence) > Arrangements of heads > Raising, lowering, traversing otherwise than for transducing, arresting, or holding-up heads against record carriers > using automatic means (G11B3/095 takes precedence )
Of 3 combined children, 0 exist in both systems.
3 codes are CPC-only extensions.