Patent US2089338A successfully refreshed from Google Patents.
US2089338A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone system
Assignee: AT&T Inc
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Filing: 1936-03-11
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Granted: 1937-08-10
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Expires: 1956-03-11
Abstract
No abstract record available.
Inventors
- 👤 Warren W Carpenter
- 👤 Alfred E Hague
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:20
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0004
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) | 1940-08-09 | 1941-02-08 | 1941-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1944-08-09 | 1945-02-08 | 1945-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1948-08-09 | 1949-02-08 | 1949-08-10 | $7700.00 | Window Closed / Lapsed |