US2428039A
Expired / Lapsed
US
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Assignee: STC PLC
•
Filing: 1942-06-20
•
Granted: 1947-09-30
•
Expires: 1962-06-20
Abstract
No abstract record available.
Inventors
- 👤 George T Royden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:08
CPC Classifications
H; H03; H03G; H03G7/00; H03G7/02; H03G7/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2281644A
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US2343207A
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US2269408A
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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) | 1950-09-29 | 1951-03-31 | 1951-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-09-29 | 1955-03-31 | 1955-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-09-29 | 1959-03-31 | 1959-09-30 | $7700.00 | Window Closed / Lapsed |