US2498746A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic sound recording apparatus
Assignee: Individual
•
Filing: 1944-12-19
•
Granted: 1950-02-28
•
Expires: 1964-12-19
Abstract
No abstract record available.
Inventors
- 👤 Joseph B Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:40
CPC Classifications
G; G11; G11B; G11B5/00; G11B23/00; G11B23/02; G11B5/48
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US822222A
Cited
US893277A
Cited
GB191111183A
Cited
US2247847A
Cited
US2265879A
Cited
US2293229A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-02-27 | 1953-08-29 | 1954-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-02-27 | 1957-08-29 | 1958-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-02-27 | 1961-08-29 | 1962-02-28 | $7700.00 | Window Closed / Lapsed |