| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 41 | |
| #2 | Canada | 2 |
| # | Industry | |
|---|---|---|
| #1 | Civil engineering |
| # | Technology | |
|---|---|---|
| #1 | Construction of roads | |
| #2 | Platform constructions |
| # | Name | Total Patents |
|---|---|---|
| #1 | Robertson Robert R | 38 |
| #2 | Woodward Edwin C | 2 |
| #3 | Hayes Robertson | 1 |
| #4 | Robertson Edgar C | 1 |
| #5 | Landeen Bernard N | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US2121303A | Double dowel bar expansion joint | |
| US2145951A | Road contraction joint | |
| US2147269A | Road joint end seal | |
| US2160520A | Road guard fence | |
| US2160519A | Road guard fence | |
| US2153394A | Transverse road joint | |
| US2138615A | Road joint end seal | |
| US2149466A | Expansion joint and cap | |
| US2158637A | Road joint | |
| US2121302A | Road joint brace | |
| US2149467A | Center joint | |
| US2142803A | Road reflector | |
| US2153393A | Road seal | |
| US2145936A | Traffic lane divider | |
| US2164084A | Road guard fence | |
| US2121573A | Expansion joint | |
| US2141559A | Expanision joint with peripheral seal | |
| US2139465A | Contraction joint with peripheral seal | |
| US2144815A | Longitudinal or center joint and method of road widening | |
| US2172773A | Expansion joint with asphalt and copper seal |