Issued Patents All Time
Showing 1–6 of 6 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8276886 | Combined guardrail and cable safety systems | Charles R. Norton, Elzard Sikkema, Brian E. Smith | 2012-10-02 |
| 8157471 | Combined guardrail and cable safety systems | Peter Bergendahl, Charles R. Norton, Elzard Sikkema | 2012-04-17 |
| 7988133 | Combined guardrail and cable safety systems | Charles R. Norton, Elzard Sikkema, Brian E. Smith | 2011-08-02 |
| 7686535 | Combined guardrail and cable safety systems | Peter Bergendahl, Charles R. Norton, Elzard Sikkema | 2010-03-30 |
| 7544009 | Combined guardrail and cable safety systems | Peter Bergendahl, Chuck Norton, Elzard Sikkema | 2009-06-09 |
| 7249908 | Combined guardrail and cable safety systems | Peter Bergendahl, Chuck Norton, Elzard Sikkema | 2007-07-31 |