US3539933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switchover logic circuit
Assignee: AT&T Inc
•
Filing: 1967-09-07
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Granted: 1970-11-10
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Expires: 1987-09-07
Abstract
No abstract record available.
Inventors
- 👤 Herbert J White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:29
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/16; G06F11/1604; H; H03; H03K; H03K5/00; H04; H04L; H04L7/00; H04L7/0079; H04L7/0083; G06F11/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2906869A
Cited
US3034065A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-09 | 1974-05-11 | 1974-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-09 | 1978-05-11 | 1978-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-09 | 1982-05-11 | 1982-11-10 | $7700.00 | Window Closed / Lapsed |