Patent US2981932A successfully refreshed from Google Patents.
US2981932A
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Magnetic memory device and method of manufacture
Assignee: AT&T Inc
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Filing: 1955-12-22
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Granted: 1961-04-25
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Expires: 1975-12-22
Abstract
No abstract record available.
Inventors
- 👤 Duncan H Looney
- 👤 Robert H Meinken
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:34
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/26; C04B35/2608; C04B35/2625; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49069
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2457806A
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US2743507A
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US2746130A
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US2700150A
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US2724103A
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US2792563A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-24 | 1964-10-24 | 1965-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-24 | 1968-10-24 | 1969-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-24 | 1972-10-24 | 1973-04-25 | $7700.00 | Window Closed / Lapsed |