US2347777A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signaling circuit
Assignee: AT&T Inc
•
Filing: 1941-12-23
•
Granted: 1944-05-02
•
Expires: 1961-12-23
Abstract
No abstract record available.
Inventors
- 👤 Clarence D Hanscom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:03
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04M; H04M1/00; H04M1/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1947-05-02 | 1947-11-01 | 1948-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1951-05-02 | 1951-11-01 | 1952-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1955-05-02 | 1955-11-01 | 1956-05-02 | $7700.00 | Window Closed / Lapsed |