US2666977A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reversible semiconductor and method of making it
Assignee: AT&T Inc
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Filing: 1948-12-31
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Granted: 1954-01-26
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Expires: 1968-12-31
Abstract
No abstract record available.
Inventors
- 👤 William G Pfann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:13
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/26; H; H10; H10P; H10P95/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-01-25 | 1957-07-27 | 1958-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-01-25 | 1961-07-27 | 1962-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-01-25 | 1965-07-27 | 1966-01-26 | $7700.00 | Window Closed / Lapsed |