US2913246A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording surface
Assignee: International Business Machines Corp
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Filing: 1954-04-19
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Granted: 1959-11-17
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Expires: 1974-04-19
Abstract
No abstract record available.
Inventors
- 👤 Jacob J Hagopian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:18
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/74; G11B5/82
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) | 1962-11-16 | 1963-05-18 | 1963-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-11-16 | 1967-05-18 | 1967-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-11-16 | 1971-05-18 | 1971-11-17 | $7700.00 | Window Closed / Lapsed |