Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4750559 | Retrievable anchor assembly | Donald Roy Greenlee | 1988-06-14 |
| 4702313 | Slip and slip assembly for well tools | Donald Roy Greenlee | 1987-10-27 |
| 4691775 | Isolation valve with frangible flapper element | Gary D. Ellis | 1987-09-08 |
| 4688634 | Running and setting tool for well packers | Donald E. Ritchie | 1987-08-25 |