US1412405A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for testing transmitters
Assignee: AT&T Inc
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Filing: 1920-11-02
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Granted: 1922-04-11
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Expires: 1940-11-02
Abstract
No abstract record available.
Inventors
- 👤 Raymond R Herrmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:11
CPC Classifications
H; H04; H04R; H04R29/00
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) | 1925-04-10 | 1925-10-10 | 1926-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1929-04-10 | 1929-10-10 | 1930-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1933-04-10 | 1933-10-10 | 1934-04-11 | $7700.00 | Window Closed / Lapsed |