Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5321881 | Method of installing a shoe seal for floating roof of storage tank | David W. Otto | 1994-06-21 |
| 5103992 | Shoe seal for floating roof of storage tank, and method of installing same | David W. Otto | 1992-04-14 |
| 5078293 | Shoe seal for lightweight floating roof | — | 1992-01-07 |