US2773941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hearing aid apparatus
Assignee: American Danish Oticon AS
•
Filing: 1952-07-15
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Granted: 1956-12-11
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Expires: 1972-07-15
Abstract
No abstract record available.
Inventors
- 👤 Henry E Christiansen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:27
CPC Classifications
H; H04; H04R; H04R11/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-12-11 | 1960-06-11 | 1960-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-12-11 | 1964-06-11 | 1964-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-12-11 | 1968-06-11 | 1968-12-11 | $7700.00 | Window Closed / Lapsed |