US2452568A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switching device
Assignee: AT&T Inc
•
Filing: 1943-10-01
•
Granted: 1948-11-02
•
Expires: 1963-10-01
Abstract
No abstract record available.
Inventors
- 👤 Henry C Harrison
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:22
CPC Classifications
H; H01; H01H; H01H50/00; H01H50/54; H01H50/56; H01H50/58; H01H51/00; H01H51/02; H01H51/04; H01H51/06; H01H51/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US752150A
Cited
US1972941A
Cited
US2116173A
Cited
US2241156A
Cited
US2172322A
Cited
US2305450A
Cited
US2292489A
Cited
US2307868A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-11-02 | 1952-05-03 | 1952-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-11-02 | 1956-05-03 | 1956-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-11-02 | 1960-05-03 | 1960-11-02 | $7700.00 | Window Closed / Lapsed |