US2765044A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sound filtering apparatus
Assignee: Individual
•
Filing: 1952-07-16
•
Granted: 1956-10-02
•
Expires: 1972-07-16
Abstract
No abstract record available.
Inventors
- 👤 Hatte Jacques Louis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:45
CPC Classifications
F; F01; F01N; F01N1/00; F01N1/02; G; G10; G10K; G10K11/00; G10K11/02; G10K11/04; F01N2490/00; F01N2490/15; F01N2490/155
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1692317A
Cited
US1781469A
Cited
US1874326A
Cited
US1909394A
Cited
GB398359A
Cited
US1910672A
Cited
US2030178A
Cited
GB432372A
Cited
US2401570A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-10-02 | 1960-04-02 | 1960-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-02 | 1964-04-02 | 1964-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-02 | 1968-04-02 | 1968-10-02 | $7700.00 | Window Closed / Lapsed |