US2298519A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone system
Assignee: AT&T Inc
•
Filing: 1940-06-21
•
Granted: 1942-10-13
•
Expires: 1960-06-21
Abstract
No abstract record available.
Inventors
- 👤 Richard J Tillman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:46
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/42
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) | 1945-10-12 | 1946-04-13 | 1946-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-10-12 | 1950-04-13 | 1950-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-10-12 | 1954-04-13 | 1954-10-13 | $7700.00 | Window Closed / Lapsed |