Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date | Approx Value ⓘ |
|---|---|---|---|---|
| 5131471 | Single well injection and production system | John H. Duerksen, Donald J. Anderson, Doug J. McCallum | 1992-07-21 | $54,590,000 |
| 5024275 | Method of recovering hydrocarbons using single well injection/production system | Donald J. Anderson, John H. Duerksen, Doug J. McCallum | 1991-06-18 | $62,004,000 |