DS

Douglas B. Steffen

📍 Griswold, IA: #5 of 9 inventorsTop 60%
🗺 Iowa: #6,094 of 15,303 inventorsTop 40%
Overall (All Time): #2,287,978 of 4,157,543Top 60%
2
Patents All Time

Issued Patents All Time

Showing 1–2 of 2 patents

Patent #TitleCo-InventorsDate
5431117 Seed drum row shutoff for planter Bruce J. Steffens, Louis Stirek 1995-07-11
5044449 Flex tine soil mulcher Louis Stirek, Bruce J. Steffens 1991-09-03