| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United Kingdom | 4 | |
| #2 | Australia | 3 | |
| #3 | New Zealand | 2 | |
| #4 | Czechia | 1 | |
| #5 | Finland | 1 | |
| #6 | Hungary | 1 | |
| #7 | Mexico | 1 | |
| #8 | Norway | 1 | |
| #9 | Poland | 1 |
| # | Industry | |
|---|---|---|
| #1 | Civil engineering | |
| #2 | Mechanical elements | |
| #3 | Environmental technology |
| # | Name | Total Patents |
|---|---|---|
| #1 | Frost Douglas Robert David | 10 |
| #2 | Frost Douglas R D | 1 |
| Publication | Filing date | Title |
|---|---|---|
| AU4742299A | Discharge valve | |
| CZ9903744A3 | Discharge valve apparatus | |
| GB2087045A | A refill valve for a water cistern | |
| GB2014682A | Valve coupling for a water cistern | |
| GB2041421A | Syphon unit for flushing cisterns | |
| GB1590630A | Fluid flow silencing device |