| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Denmark | 7 | |
| #2 | Canada | 6 | |
| #3 | Austria | 5 | |
| #4 | Switzerland | 5 | |
| #5 | Spain | 5 | |
| #6 | France | 2 | |
| #7 | United Kingdom | 1 |
| # | Industry | |
|---|---|---|
| #1 | Transport | |
| #2 | Audio-visual technology |
| # | Technology | |
|---|---|---|
| #1 | Aeroplanes | |
| #2 | Marine propulsion | |
| #3 | Advertising |
| # | Name | Total Patents |
|---|---|---|
| #1 | Flettner Anton | 22 |
| #2 | Anton Flettner | 4 |
| Publication | Filing date | Title |
|---|---|---|
| ES146588A1 | A helicopter with a pair of rotors that turn in the opposite direction. | |
| ES131440A1 | Perfeccionamientos in airplanes with rotating wings. | |
| GB148172A | Improvements relating to the steering planes of air-craft | |
| CA240996A | Propeller | |
| CA349216A | Aircraft | |
| CA232284A | Device for steering air crafts | |
| CA234688A | Device for steering ships | |
| CA240997A | Marine steering device | |
| CA287419A | Ventilator |