Patent US2538027A successfully refreshed from Google Patents.
US2419957A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical protective alarm system
Assignee: ADT Security Systems Inc
•
Filing: 1943-07-09
•
Granted: 1947-05-06
•
Expires: 1963-07-09
Abstract
No abstract record available.
Inventors
- 👤 Herbert M Laford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:07
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US492478A
Cited
US819873A
Cited
US1114565A
Cited
US1009285A
Cited
US1181419A
Cited
US1238823A
Cited
US1365693A
Cited
US1377939A
Cited
US1709097A
Cited
US1562574A
Cited
US1881832A
Cited
US1732276A
Cited
US2250834A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-05-05 | 1950-11-04 | 1951-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-05-05 | 1954-11-04 | 1955-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-05-05 | 1958-11-04 | 1959-05-06 | $7700.00 | Window Closed / Lapsed |