Patent DE2547552A1 successfully refreshed from Google Patents.
US2939317A
Expired / Lapsed
US
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Variable resistance semiconductive devices
Assignee: AT&T Inc
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Filing: 1955-10-31
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Granted: 1960-06-07
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Expires: 1975-10-31
Abstract
No abstract record available.
Inventors
- 👤 Warren P Mason
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:08
CPC Classifications
G; G01; G01P; G01P15/00; G01P15/02; G01P15/08; G01P15/12; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/18; G01D5/183; G01D5/185; H; H04; H04R; H04R23/00
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) | 1963-06-07 | 1963-12-07 | 1964-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-07 | 1967-12-07 | 1968-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-07 | 1971-12-07 | 1972-06-07 | $7700.00 | Window Closed / Lapsed |