Individual holder
HELVERSEN FREDERICK D
3 granted patents·119 citations·filing 1976–1986
Individually held — no corporate assignee on record.
Top patents by PatentIndex Score
3 records- 0187US4074441ARotary through dryer having multiple vacuum chambers and associated heatersHELVERSEN FREDERICK D·Filed 1976·Granted Feb 21, 1978·60 cites·13 claims
- 0284US4249654AHydrogen storage apparatusHELVERSEN FREDERICK D·Filed 1979·Granted Feb 10, 1981·48 cites·12 claims
- 0343US4678368ACanal covering system and method of installing sameHELVERSEN FREDERICK D·Filed 1986·Granted Jul 7, 1987·11 cites·10 claims
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Counts cover granted patents and pending applications in the PatentIndex corpus. How scoring works →