Issued Patents All Time
Showing 1–25 of 30 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10256617 | Handhole assembly | David E. Erickson | 2019-04-09 |
| 8322109 | Multi-cage spacer | — | 2012-12-04 |
| 7727326 | Varied length fibers in a brittle material | Clifford N. MacDonald | 2010-06-01 |
| 7682104 | Culvert inlet protection device | Matthew A. Wassman, Richard M. Odland | 2010-03-23 |
| 7581655 | Pullbox assembly | — | 2009-09-01 |
| D574933 | Sanitary storm and catch basin trap | — | 2008-08-12 |
| D572802 | Sanitary storm and catch basin trap | — | 2008-07-08 |
| 7361834 | Electric handhole/pullbox access cover | David E. Erickson | 2008-04-22 |
| 7328538 | Rebar spacer | — | 2008-02-12 |
| D559959 | Sanitary storm and catch basin trap | — | 2008-01-15 |
| D559958 | Sanitary storm and catch basin trap | — | 2008-01-15 |
| 7309420 | Sanitary, storm and catch basin trap with filter insert | — | 2007-12-18 |
| D557385 | Sanitary storm and catch basin trap | — | 2007-12-11 |
| D556865 | Catch basin flow diverter | — | 2007-12-04 |
| 7300573 | Catch basin filter | — | 2007-11-27 |
| 7132045 | Sanitary, storm and catch basin trap with filter insert | — | 2006-11-07 |
| 7059806 | Hole former for an invert | — | 2006-06-13 |
| 7004190 | Outside drop for manhole | — | 2006-02-28 |
| 6910309 | Cage spacer | — | 2005-06-28 |
| 6899310 | Cage spacer | — | 2005-05-31 |
| 6881899 | Pullbox assembly | — | 2005-04-19 |
| 6758021 | Cage spacer | — | 2004-07-06 |
| 6695002 | Outside drop for manhole | — | 2004-02-24 |
| 6347781 | Concrete hole former with embedded gasket | — | 2002-02-19 |
| 6226928 | Caustic fluid blocking member in the base of a manhole | — | 2001-05-08 |