US2849533A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Headphone device
Assignee: Dictaphone Corp
•
Filing: 1951-12-12
•
Granted: 1958-08-26
•
Expires: 1971-12-12
Abstract
No abstract record available.
Inventors
- 👤 Mattia Alfred L Di
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:37
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/02; H04M1/04; H04M1/05
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2385221A
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US1600296A
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US582901A
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US1847607A
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US2419471A
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US1148849A
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US1245217A
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US1620367A
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US1804688A
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US1811558A
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US1964604A
Cited
US2142407A
Cited
US2498960A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-08-25 | 1962-02-24 | 1962-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-08-25 | 1966-02-24 | 1966-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-08-25 | 1970-02-24 | 1970-08-26 | $7700.00 | Window Closed / Lapsed |