Portfolio comparison
Hovercraft Development Ltd vs William F. Semple
Side-by-side portfolio analysis — patents indexed, year ranges, and activity timeline.
Company A
Hovercraft Development Ltd
Patents indexed
1
Year range
1967
Most recent
1967
automotiveaerospacemechanicaltransportation
Top Patents1 enriched
US 3321037· 1967
How Hovercrafts Use Flexible Skirts to Ride on Air
Activity by Decade
1960s1
Top Patents1 enriched
US 98304· 1869
William Semple's 1869 Patent for Improved Chewing Gum
Activity by Decade
1860s1
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