Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6516572 | Slate and interlayment roof and a method of preparing the same | David Nowacek | 2003-02-11 |
| 6148578 | Slate and interlayment roof and a method of preparing the same | David Nowacek | 2000-11-21 |