US2496642A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Subscriber telephone set double connection signal
Assignee: AT&T Inc
•
Filing: 1945-01-20
•
Granted: 1950-02-07
•
Expires: 1965-01-20
Abstract
No abstract record available.
Inventors
- 👤 Oscar A Shann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:10
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/02; H04M1/22; H04M1/68
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1646996A
Cited
US1845017A
Cited
US1897106A
Cited
US1955972A
Cited
US1985172A
Cited
US2294809A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-02-06 | 1953-08-08 | 1954-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-02-06 | 1957-08-08 | 1958-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-02-06 | 1961-08-08 | 1962-02-07 | $7700.00 | Window Closed / Lapsed |