Inventor · disambiguated record
Douglas F. Koelfgen
Also filed as: KOELFGEN DOUGLAS · KOELFGEN DOUGLAS F
2 granted patents·1 pending application·202 citations·filing 1982–2013
68Inventor score
Technology areasB01D
Top patents by PatentIndex Score
3 records- 0188US5548893ASpin-on oil filter replacement elementFiled 1995·Granted Aug 27, 1996·187 cites·16 claims
- 0244US4401563AOil filter cartridge for motorcyclesKOELFGEN DOUGLAS·Filed 1982·Granted Aug 30, 1983·15 cites·4 claims
- 0339US2013256242A1Oil Filter/CoolerKOELFGEN DOUGLAS F·Filed 2013·Application pending·0 cites
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →