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Patent US1325879A successfully refreshed from Google Patents.
US1325879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum-tube circuits.
Assignee: AT&T Inc
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Filing: 1916-12-28
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Granted: 1919-12-23
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Expires: 1936-12-28
Abstract
No abstract record available.
Inventors
- 👤 Harold W Nichols
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:10
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/08
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) | 1922-12-22 | 1923-06-23 | 1923-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1926-12-22 | 1927-06-23 | 1927-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1930-12-22 | 1931-06-23 | 1931-12-23 | $7700.00 | Window Closed / Lapsed |