US2505566A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signaling system
Assignee: AT&T Inc
•
Filing: 1945-07-23
•
Granted: 1950-04-25
•
Expires: 1965-07-23
Abstract
No abstract record available.
Inventors
- 👤 Mitchell Doren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:56
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/42
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1597763A
Cited
US1695840A
Cited
US1867209A
Cited
US1972985A
Cited
US2165924A
Cited
US2216610A
Cited
US2329234A
Cited
US2413440A
Cited
US2352142A
Cited
US2421022A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-04-24 | 1953-10-24 | 1954-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-04-24 | 1957-10-24 | 1958-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-04-24 | 1961-10-24 | 1962-04-25 | $7700.00 | Window Closed / Lapsed |