| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Canada | 11 | |
| #2 | United States | 11 |
| # | Industry | |
|---|---|---|
| #1 | Packaging and shipping | |
| #2 | Machines |
| # | Technology | |
|---|---|---|
| #1 | Transport or storage devices | |
| #2 | Postal sorting | |
| #3 | Unspecified technologies |
| # | Name | Total Patents |
|---|---|---|
| #1 | Bridgman George A | 8 |
| #2 | Riper Stanley V Van | 4 |
| #3 | Warren Cutler Joseph | 3 |
| #4 | Cutler Joseph Warren | 3 |
| #5 | Howard Lester | 2 |
| #6 | Harper John D | 1 |
| #7 | Lester Howard | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US2299896A | Mail chute | |
| US2209070A | Mail chute construction | |
| US2025193A | Mail chute | |
| US2042500A | Mail chute | |
| US2019557A | Mail chute | |
| US1976251A | Letter drop for mail chutes | |
| US1969848A | Mail chute | |
| US1907906A | Mail chute | |
| US1895069A | Mail chute | |
| US1929109A | Mail sorting chute | |
| US1794104A | Mail chute | |
| CA356924A | Mail chute | |
| CA346355A | Letter drop | |
| CA356923A | Mail chute | |
| CA318458A | Mail chute closure | |
| CA320375A | Mail chute | |
| CA396945A | Mail chute | |
| CA339220A | Mail chute | |
| CA351356A | Mail chute | |
| CA347178A | Mail chute |