Patent US2299487A successfully refreshed from Google Patents.
US2299487A
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US
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Electric wave transmission system
Assignee: AT&T Inc
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Filing: 1941-05-03
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Granted: 1942-10-20
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Expires: 1961-05-03
Abstract
No abstract record available.
Inventors
- 👤 Hilbert R Moore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:29
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/54; H04B14/00; H04B14/002; H04B14/006; H04B2203/00; H04B2203/54; H04B2203/5429; H04B2203/5437
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1945-10-19 | 1946-04-20 | 1946-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-10-19 | 1950-04-20 | 1950-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-10-19 | 1954-04-20 | 1954-10-20 | $7700.00 | Window Closed / Lapsed |