Portfolio comparison
Hovercraft Development Ltd vs Marvin C. Stone
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 375962· 1888
How the Modern Paper Drinking Straw Was Invented
Activity by Decade
1880s1
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