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US2591937A
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Selective calling system
Assignee: Automatic Electric Laboratories Inc
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Filing: 1947-05-01
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Granted: 1952-04-08
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Expires: 1967-05-01
Abstract
No abstract record available.
Inventors
- 👤 Roswell H Herrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:29
CPC Classifications
H; H04; H04W; H04W88/00; H04W88/02; H04W88/022; H04W88/025; H04W88/027
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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GB172321A
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US2047900A
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GB261384A
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US2052581A
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US2148578A
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US2168198A
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US2255162A
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US2368953A
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US2388531A
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US2441145A
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US2457149A
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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) | 1955-04-08 | 1955-10-08 | 1956-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-04-08 | 1959-10-08 | 1960-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-04-08 | 1963-10-08 | 1964-04-08 | $7700.00 | Window Closed / Lapsed |