US2990539A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistor amplifiers
Assignee: International Business Machines Corp
•
Filing: 1955-05-25
•
Granted: 1961-06-27
•
Expires: 1975-05-25
Abstract
No abstract record available.
Inventors
- 👤 James B Mackay
- 👤 Joseph C Logue
- 👤 Raymond W Emery
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 02:03
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/45; H03K17/00; H03K17/51; H03K17/56; H03K17/72; H03K17/73
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2605306A
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US2741757A
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US2595208A
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US2686262A
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US2691154A
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US2748275A
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US2695993A
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US2739300A
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US2798169A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-06-26 | 1964-12-26 | 1965-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-26 | 1968-12-26 | 1969-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-26 | 1972-12-26 | 1973-06-27 | $7700.00 | Window Closed / Lapsed |