US2088750A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Answer-back device for machine switching printing telegraph exchange systems
Assignee: AT&T Inc
•
Filing: 1936-01-18
•
Granted: 1937-08-03
•
Expires: 1956-01-18
Abstract
No abstract record available.
Inventors
- 👤 Fullerton S Kinkead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 00:40
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/02; H04L12/06
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1940-08-02 | 1941-02-01 | 1941-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1944-08-02 | 1945-02-01 | 1945-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1948-08-02 | 1949-02-01 | 1949-08-03 | $7700.00 | Window Closed / Lapsed |