US1188531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Duplex wireless system.
Assignee: AT&T Inc
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Filing: 1915-09-27
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Granted: 1916-06-27
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Expires: 1935-09-27
Abstract
No abstract record available.
Inventors
- 👤 John R Carson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 03:08
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/50
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) | 1919-06-27 | 1919-12-27 | 1920-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1923-06-27 | 1923-12-27 | 1924-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1927-06-27 | 1927-12-27 | 1928-06-27 | $7700.00 | Window Closed / Lapsed |