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US2835334A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Speaker unit
Assignee: Individual
•
Filing: 1954-05-06
•
Granted: 1958-05-20
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Expires: 1974-05-06
Abstract
No abstract record available.
Inventors
- 👤 Mcdonald James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:10
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/02; H04R1/026; H04R1/20; H04R1/22; H04R1/28; H04R1/2807; H04R1/283; H04R1/2834; H04R2205/00; H04R2205/021
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) | 1961-05-19 | 1961-11-18 | 1962-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-05-19 | 1965-11-18 | 1966-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-05-19 | 1969-11-18 | 1970-05-20 | $7700.00 | Window Closed / Lapsed |