Patent US2421750A successfully refreshed from Google Patents.
US2421750A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic wire storage unit
Assignee: AT&T Inc
•
Filing: 1944-12-20
•
Granted: 1947-06-10
•
Expires: 1964-12-20
Abstract
No abstract record available.
Inventors
- 👤 Danforth K Gannett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:15
CPC Classifications
G; G11; G11B; G11B25/00; G11B25/08; Y; Y10; Y10S; Y10S425/00; Y10S425/04
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US708184A
Cited
US1400508A
Cited
US1609438A
Cited
US1795923A
Cited
US1960743A
Cited
US2151629A
Cited
US2224854A
Cited
US2339762A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-06-09 | 1950-12-09 | 1951-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-06-09 | 1954-12-09 | 1955-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-06-09 | 1958-12-09 | 1959-06-10 | $7700.00 | Window Closed / Lapsed |