Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5826669 | Drilling fluid loss prevention and lubrication additive | Peter L. Zaleski, David J. Derwin, Donald J. Weintritt | 1998-10-27 |
| 4687054 | Linear electric motor for downhole use | Larry B. Underwood | 1987-08-18 |