Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5745047 | Downhole electricity transmission system | Wilhelmus Johannes Martinus Der Kinderen | 1998-04-28 |
| 5535828 | Wellbore system with retrievable valve body | Wilhelmus Johannes Martinus Der Kinderen | 1996-07-16 |