US2709722A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Service observing on toll cords and trunks
Assignee: AT&T Inc
•
Filing: 1952-10-02
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Granted: 1955-05-31
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Expires: 1972-10-02
Abstract
No abstract record available.
Inventors
- 👤 Victor E Rosene
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:46
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/20; H04Q1/22
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1641453A
Cited
US1691554A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-05-30 | 1958-11-29 | 1959-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-05-30 | 1962-11-29 | 1963-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-05-30 | 1966-11-29 | 1967-05-31 | $7700.00 | Window Closed / Lapsed |