| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Germany | 3 | |
| #2 | United Kingdom | 3 | |
| #3 | Canada | 2 | |
| #4 | Switzerland | 2 | |
| #5 | France | 2 | |
| #6 | United States | 2 | |
| #7 | Austria | 1 | |
| #8 | Denmark | 1 | |
| #9 | Norway | 1 |
| # | Industry | |
|---|---|---|
| #1 | Machine tools | |
| #2 | Machines |
| # | Technology | |
|---|---|---|
| #1 | Perforating | |
| #2 | Unspecified technologies |
| # | Name | Total Patents |
|---|---|---|
| #1 | Hellberg Gustav Sigvard | 2 |
| #2 | Hellberg Gustav S | 2 |
| #3 | Hellberg Gustav Sigvald | 1 |
| #4 | Sigvard Hellberg Gustav | 1 |
| #5 | Sigvard Hellberg | 1 |
| #6 | Sigvald Hellberg Gustav | 1 |
| Publication | Filing date | Title |
|---|---|---|
| GB923029A | Perforating machine for producing tear-off perforations | |
| GB886484A | Method and means for making perforations | |
| US3198045A | Method of perforating webs containing resin | |
| GB796300A | Method and means for the perforation of paper and the like | |
| CA569372A | Method and means for the perforation of paper and the like | |
| CA701657A | Method and means for making perforations |