US2640099A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hearing aid test structure
Assignee: OTARION Inc
•
Filing: 1948-07-31
•
Granted: 1953-05-26
•
Expires: 1968-07-31
Abstract
No abstract record available.
Inventors
- 👤 Denison B Hull
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:12
CPC Classifications
H; H04; H04R; H04R25/00; H04R25/04; H04R25/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US964995A
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US2406583A
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US2424422A
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US2482288A
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US2450657A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-25 | 1956-11-24 | 1957-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-25 | 1960-11-24 | 1961-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-25 | 1964-11-24 | 1965-05-26 | $7700.00 | Window Closed / Lapsed |