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Patent US2988735A successfully refreshed from Google Patents.
US2988735A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic data storage
Assignee: Research Corp
•
Filing: 1955-03-17
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Granted: 1961-06-13
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Expires: 1975-03-17
Abstract
No abstract record available.
Inventors
- 👤 Robert R Everett
- 👤 Robert L Walquist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:01
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/10527; G11B2220/00; G11B2220/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2563742A
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US2550116A
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US2540654A
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US2570442A
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US2551104A
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US2614169A
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US2713676A
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US2698427A
Cited
US2817072A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-06-12 | 1964-12-12 | 1965-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-12 | 1968-12-12 | 1969-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-12 | 1972-12-12 | 1973-06-13 | $7700.00 | Window Closed / Lapsed |