| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Germany | 5 | |
| #2 | France | 4 | |
| #3 | Belgium | 3 | |
| #4 | United Kingdom | 3 | |
| #5 | Australia | 1 | |
| #6 | Japan | 1 | |
| #7 | United States | 1 | |
| #8 | South Africa | 1 |
| # | Industry | |
|---|---|---|
| #1 | Civil engineering | |
| #2 | Packaging and shipping |
| # | Name | Total Patents |
|---|---|---|
| #1 | Wolters Tjako Aaldrik | 2 |
| #2 | Koning Jan De Dipl Ing | 2 |
| #3 | Der Dipl-Ing Veen Romke Van | 1 |
| #4 | De Dipl-Ing Koning Jan | 1 |
| #5 | Wolters T | 1 |
| #6 | Petorusu Yohanesu Herumanusu N | 1 |
| #7 | De Koning Jan | 1 |
| #8 | Van Zeggelaar Gerrit H | 1 |
| #9 | Zeggelaar Gerrit Hendrik Van | 1 |
| #10 | Aaldrik Wolters Tjako | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US4175342A | Suction dredger | |
| ZA7400625B | Earth dredger | |
| GB1422021A | Suction dredger | |
| GB1422023A | Suction dredger | |
| DE2366140B1 | Suction dredger |