Issued Patents All Time
Showing 1–10 of 10 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11220862 | Step ladder | Dennis D. Simpson, Ben Williams, Yongxue Lu | 2022-01-11 |
| 10648234 | Step ladder | Dennis D. Simpson, Ben Williams, Yongxue Lu | 2020-05-12 |
| D840055 | Step ladder | Dennis D. Simpson, Benjamin P. Williams, Yongxue Lu | 2019-02-05 |
| D710031 | Step stool | Dennis D. Simpson, Louis F. Polk, III, Jason J. Ness | 2014-07-29 |
| D687614 | Cart | Dennis D. Simpson, Louis F. Polk, III, Jason J. Ness | 2013-08-06 |
| 7887141 | Articulated utility cart | Frank Pieschel, Robert J. Jantschek, Dennis D. Simpson | 2011-02-15 |
| 7818865 | Method of making a dumping utility cart | Frank Pieschel, Craig L. Stewart, Dennis D. Simpson | 2010-10-26 |
| D554771 | Stepladder | Jon Sommers, Kirby Howard | 2007-11-06 |
| D548364 | Stepladder | Jon Sommers, Kirby Howard | 2007-08-07 |
| D506762 | Portable air compressor | Frank Pieschel, Jon Sommers | 2005-06-28 |