Top Inventors at Sigma Tool & Machine All Time
| Rank | Name | Patents |
|---|---|---|
| 1 | Herbert E. Leistner | 6 |
| 2 | Volkmar W. Leistner | 5 |
| 3 | Walter H. Leistner | 4 |
| #4 | Martin Leistner | 3 |
| #5 | Carlo Stagnoli | 2 |
| #6 | Siegfried Figge | 2 |
| #7 | Garry Randall Olson | 1 |
| #8 | Paul D. Green | 1 |
| #9 | Richard Pfeiffer | 1 |
| #10 | Sung Hsiang Liu | 1 |