| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Australia | 1 | |
| #2 | Belgium | 1 | |
| #3 | Brazil | 1 | |
| #4 | Canada | 1 | |
| #5 | Denmark | 1 | |
| #6 | EPO (European Patent Office) | 1 | |
| #7 | Spain | 1 | |
| #8 | Finland | 1 | |
| #9 | Italy | 1 | |
| #10 | Republic of Korea | 1 | |
| #11 | Monaco | 1 | |
| #12 | Norway | 1 | |
| #13 | New Zealand | 1 | |
| #14 | WIPO (World Intellectual Property Organization) | 1 | |
| #15 | South Africa | 1 |
| # | Industry | |
|---|---|---|
| #1 | Control |
| # | Technology | |
|---|---|---|
| #1 | Alarm systems |
| # | Name | Total Patents |
|---|---|---|
| #1 | Williams Harold B | 5 |
| #2 | Williams Harold | 5 |
| #3 | Williams H | 2 |
| #4 | Williams H B | 1 |
| Publication | Filing date | Title |
|---|---|---|
| KR880002492B1 | Dual frequency anti-theft system | |
| BE893006A | Dual frequency antitheft system - transmits two different radio frequencies for summing and reradiation by antitheft tag transponder | |
| CA1190970A | Dual frequency anti-theft system |