Patent US2375136A successfully refreshed from Google Patents.
US2375136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone system
Assignee: AT&T Inc
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Filing: 1944-05-05
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Granted: 1945-05-01
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Expires: 1964-05-05
Abstract
No abstract record available.
Inventors
- 👤 Rhoads Charles Stanley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:20
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/42; H04M3/50; H04M3/51; H04M3/52
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) | 1948-04-30 | 1948-10-30 | 1949-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1952-04-30 | 1952-10-30 | 1953-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1956-04-30 | 1956-10-30 | 1957-05-01 | $7700.00 | Window Closed / Lapsed |