| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Greece | 4 | |
| #2 | United States | 4 | |
| #3 | Belgium | 3 | |
| #4 | Canada | 3 | |
| #5 | Portugal | 3 | |
| #6 | Australia | 2 | |
| #7 | Switzerland | 2 | |
| #8 | Germany | 2 | |
| #9 | Spain | 2 | |
| #10 | France | 2 | |
| #11 | United Kingdom | 2 | |
| #12 | Italy | 2 | |
| #13 | Luxembourg | 2 | |
| #14 | Sweden | 2 | |
| #15 | EPO (European Patent Office) | 1 |
| # | Industry | |
|---|---|---|
| #1 | Machines | |
| #2 | Environmental technology | |
| #3 | Packaging and shipping |
| # | Name | Total Patents |
|---|---|---|
| #1 | Thissen Christopher P | 19 |
| #2 | Tweet Milford James | 7 |
| #3 | Hatfield Ronald Dean | 7 |
| #4 | Ferwerda Jerry Jay | 7 |
| #5 | Tweet Milford J | 5 |
| #6 | Hatfield Ronald D | 5 |
| #7 | Ferwerda Jerry J | 5 |
| #8 | Tweet M | 4 |
| #9 | Thissen C | 4 |
| #10 | Ferwerda J | 4 |
| Publication | Filing date | Title |
|---|---|---|
| PT80293A | Waste water treatment apparatus | |
| AU4031485A | Water treatment apparatus | |
| US4537678A | Rotary biological contactor | |
| US4522714A | Water treatment apparatus | |
| US4284396A | Apparatus for vacuum thermoforming polymeric sheet material | |
| US4319949A | Machine for heat sealing polymeric sheets into a spiral drum | |
| CA1090017A | Waste water treatment rotor |