Patent US1974952A successfully refreshed from Google Patents.
Patent USRE20668E successfully refreshed from Google Patents.
USRE20668E
Expired / Lapsed
US
⏱️ 0.0 years remaining
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Assignee: —
•
Filing: —
•
Granted: 1938-03-08
•
Expires: 1955-03-08
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:07
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/40; F04D29/52; F04D29/54; F04D29/56; F04D29/563
Claims Analysis
Total Claims: 0
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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) | 1941-03-07 | 1941-09-06 | 1942-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-03-07 | 1945-09-06 | 1946-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-03-07 | 1949-09-06 | 1950-03-08 | $7700.00 | Window Closed / Lapsed |