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US1353976A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum-tube device
Assignee: AT&T Inc
•
Filing: 1916-03-20
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Granted: 1920-09-28
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Expires: 1936-03-20
Abstract
No abstract record available.
Inventors
- 👤 Erwin R Stoekle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:41
CPC Classifications
H; H01; H01J; H01J19/00; H01J19/02; H01J2893/00; H01J2893/0001
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) | 1923-09-28 | 1924-03-29 | 1924-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1927-09-28 | 1928-03-29 | 1928-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1931-09-28 | 1932-03-29 | 1932-09-28 | $7700.00 | Window Closed / Lapsed |