US3005052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Party line identification circuit
Assignee: AT&T Inc
•
Filing: 1957-09-16
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Granted: 1961-10-17
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Expires: 1977-09-16
Abstract
No abstract record available.
Inventors
- 👤 Robert E Powers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:30
CPC Classifications
H; H04; H04Q; H04Q5/00; H04M; H04M15/00; H04M15/36
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-10-16 | 1965-04-17 | 1965-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-10-16 | 1969-04-17 | 1969-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-10-16 | 1973-04-17 | 1973-10-17 | $7700.00 | Window Closed / Lapsed |