US2778874A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stereophonic sound system
Assignee: Warner Bros Entertainment Inc
•
Filing: 1953-04-06
•
Granted: 1957-01-22
•
Expires: 1973-04-06
Abstract
No abstract record available.
Inventors
- 👤 William A Mueller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:40
CPC Classifications
H; H04; H04S; H04S3/00; Y; Y10; Y10S; Y10S84/00; Y10S84/27
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1589139A
Cited
US2101121A
Cited
US1990388A
Cited
US1950011A
Cited
US2060204A
Cited
US2298618A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-01-22 | 1960-07-23 | 1961-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-22 | 1964-07-23 | 1965-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-22 | 1968-07-23 | 1969-01-22 | $7700.00 | Window Closed / Lapsed |