US2431797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone recording system
Assignee: Automatic Electric Laboratories Inc
•
Filing: 1943-11-05
•
Granted: 1947-12-02
•
Expires: 1963-11-05
Abstract
No abstract record available.
Inventors
- 👤 Charles F Ffolliott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:41
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/64; H04M1/65; H04M1/6515
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1546310A
Cited
US1738551A
Cited
US1973081A
Cited
US2005788A
Cited
US2200351A
Cited
US2261420A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-12-01 | 1951-06-02 | 1951-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-12-01 | 1955-06-02 | 1955-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-12-01 | 1959-06-02 | 1959-12-02 | $7700.00 | Window Closed / Lapsed |