US1898118A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signaling system
Assignee: AT&T Inc
•
Filing: 1931-11-10
•
Granted: 1933-02-21
•
Expires: 1951-11-10
Abstract
No abstract record available.
Inventors
- 👤 Charles S Demarest
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 00:02
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/444; H04Q1/446; H04Q1/4465
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) | 1936-02-21 | 1936-08-22 | 1937-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-02-21 | 1940-08-22 | 1941-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-02-21 | 1944-08-22 | 1945-02-21 | $7700.00 | Window Closed / Lapsed |