Patent US2639333A successfully refreshed from Google Patents.
US2639333A
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Magnetic recorder
Assignee: Indiana Steel Products Co
•
Filing: 1947-05-12
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Granted: 1953-05-19
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Expires: 1967-05-12
Abstract
No abstract record available.
Inventors
- 👤 Hugh A Howell
- 👤 Elmer B Offutt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:35
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/54; G11B15/00; G11B15/02; G11B15/04; G11B15/18; G11B15/22; G11B15/44; G11B15/442; G11B15/46; G11B15/48
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2086130A
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US2351005A
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US2351007A
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US2418542A
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US2467507A
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US2538892A
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US2495125A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |