Showing 1–7 of 7 inventors
| Rank | Inventor | Primary Company | Patents |
|---|---|---|---|
| 1 | Gerald R. Crawford | International Pipe Machinery | 3 |
| 2 | Craig Mericle | — | 1 |
| 2 | Willis J. Hofmeyer | Unknown | 1 |
| 2 | John D. Schumacher | — | 1 |
| 2 | Leroy McRoberts | — | 1 |
| 2 | Robert Barnum | Ibp | 1 |
| 2 | Thomas R. Trosper | Ibp | 1 |
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