Patent US2999172A successfully refreshed from Google Patents.
US2999172A
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US
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Transistor trigger circuit
Assignee: AT&T Inc
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Filing: 1957-12-20
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Granted: 1961-09-05
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Expires: 1977-12-20
Abstract
No abstract record available.
Inventors
- 👤 Jr Watson A Lawrence
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:00
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/26; H03K3/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2764688A
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US2787707A
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US2810080A
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US2850648A
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US2816230A
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US2922037A
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US2848613A
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US2838669A
Cited
US2873388A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-09-04 | 1965-03-06 | 1965-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-09-04 | 1969-03-06 | 1969-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-09-04 | 1973-03-06 | 1973-09-05 | $7700.00 | Window Closed / Lapsed |