| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United Kingdom | 6 | |
| #2 | Ireland | 4 | |
| #3 | Kenya | 3 | |
| #4 | EPO (European Patent Office) | 1 | |
| #5 | Netherlands | 1 |
| # | Industry | |
|---|---|---|
| #1 | Civil engineering |
| # | Technology | |
|---|---|---|
| #1 | Foundations and excavations | |
| #2 | Structural elements |
| # | Name | Total Patents |
|---|---|---|
| #1 | Clark Francis Sidney | 6 |
| #2 | Clark Ronald Francis | 5 |
| Publication | Filing date | Title |
|---|---|---|
| GB9619368D0 | Access cover | |
| GB9414031D0 | Access cover frames & assemblies | |
| GB9306092D0 | An adaptor frame for supporting a rectangular cover on a circular manhole opening. | |
| GB9301560D0 | Manhole container units | |
| GB8531006D0 | An access cover frame | |
| GB2093509A | An access cover and frame assembly | |
| KE3115A | Metal lintels | |
| IE821025L | Access cover | |
| IE781426L | Access cover | |
| IE44376L | Metal lintels |