US2448487A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective signaling system
Assignee: SPX Technologies Inc
•
Filing: 1945-06-14
•
Granted: 1948-08-31
•
Expires: 1965-06-14
Abstract
No abstract record available.
Inventors
- 👤 Oscar S Field
- 👤 Sedgwick N Wight
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:28
CPC Classifications
H; H04; H04Q; H04Q9/00; H04Q9/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2396211A
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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) | 1951-08-31 | 1952-03-01 | 1952-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-08-31 | 1956-03-01 | 1956-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-08-31 | 1960-03-01 | 1960-08-31 | $7700.00 | Window Closed / Lapsed |