US2719964A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic surface writing circuit utilizing magnetic cores
Assignee: AT&T Inc
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Filing: 1953-11-20
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Granted: 1955-10-04
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Expires: 1973-11-20
Abstract
No abstract record available.
Inventors
- 👤 John H Mcguigan
- 👤 Henry E Vaughan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:28
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02
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) | 1958-10-03 | 1959-04-04 | 1959-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-03 | 1963-04-04 | 1963-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-03 | 1967-04-04 | 1967-10-04 | $7700.00 | Window Closed / Lapsed |