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H. Douglas Dahl

CO Conoco: 1 patents #310 of 638Top 50%
📍 Pittsburgh, PA: #4,559 of 7,570 inventorsTop 65%
🗺 Pennsylvania: #43,221 of 74,527 inventorsTop 60%
Overall (All Time): #4,094,671 of 4,157,543Top 100%
1
Patents All Time

Issued Patents All Time

Showing 1–1 of 1 patents

Patent #TitleCo-InventorsDate
4283089 Pretreatment for fracturing coal seams Raymond L. Mazza, Ronald W. Umphrey 1981-08-11