Patent US2574944A successfully refreshed from Google Patents.
US2574944A
Expired / Lapsed
US
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All relay automatic telephone system trunk selection
Assignee: Automatic Electric Laboratories Inc
•
Filing: 1947-12-10
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Granted: 1951-11-13
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Expires: 1967-12-10
Abstract
No abstract record available.
Inventors
- 👤 John H Voss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:48
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0008
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2022503A
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US2252309A
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US2325151A
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US2333039A
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US2325877A
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US2340554A
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US2416131A
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US2431850A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-11-12 | 1955-05-14 | 1955-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-11-12 | 1959-05-14 | 1959-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-11-12 | 1963-05-14 | 1963-11-13 | $7700.00 | Window Closed / Lapsed |