| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Sweden | 5 | |
| #2 | WIPO (World Intellectual Property Organization) | 4 | |
| #3 | EPO (European Patent Office) | 3 | |
| #4 | United States | 2 | |
| #5 | Australia | 1 | |
| #6 | Canada | 1 | |
| #7 | Denmark | 1 | |
| #8 | Finland | 1 | |
| #9 | Hungary | 1 | |
| #10 | Norway | 1 | |
| #11 | Poland | 1 |
| # | Industry | |
|---|---|---|
| #1 | Machines | |
| #2 | Civil engineering | |
| #3 | Mechanical elements | |
| #4 | Thermal processes |
| # | Technology | |
|---|---|---|
| #1 | Unspecified technologies | |
| #2 | Sewers | |
| #3 | Venting or aerating devices | |
| #4 | Swimming pools | |
| #5 | Air-conditioning |
| # | Name | Total Patents |
|---|---|---|
| #1 | Persson Mats | 21 |
| #2 | Warnquist Kjell | 7 |
| Publication | Filing date | Title |
|---|---|---|
| PL356245A1 | Method and arrangement to accomplish a one−way flow | |
| WO9531622A1 | Method and arrangement in connection with containers having more than one wall | |
| EP0616659A1 | Method and device for controlling a flow of fluid | |
| EP0358672A1 | Back flow blocker in sloping pipes. |