Patent US2675362A successfully refreshed from Google Patents.
Patent US2168781A successfully refreshed from Google Patents.
US2168781A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hearing device
Assignee: Individual
•
Filing: 1937-09-21
•
Granted: 1939-08-08
•
Expires: 1957-09-21
Abstract
No abstract record available.
Inventors
- 👤 Petersen John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:20
CPC Classifications
G; G02; G02C; G02C11/00; G02C11/06; Y; Y10; Y10T; Y10T24/00; Y10T24/13; Y10T24/1371
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-08-07 | 1943-02-06 | 1943-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-08-07 | 1947-02-06 | 1947-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-08-07 | 1951-02-06 | 1951-08-08 | $7700.00 | Window Closed / Lapsed |