Patent US2421363A successfully refreshed from Google Patents.
US1580541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Locking manhole frame and cover
Assignee: Individual
•
Filing: 1925-06-29
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Granted: 1926-04-13
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Expires: 1945-06-29
Abstract
No abstract record available.
Inventors
- 👤 Warren S Sherman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:43
CPC Classifications
E; E02; E02D; E02D29/00; E02D29/12; E02D29/14; E02D29/1427; F; F16; F16J; F16J13/00; F16J13/02; F16J13/12; Y; Y10; Y10S; Y10S285/00; Y10S285/912
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) | 1929-04-12 | 1929-10-12 | 1930-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1933-04-12 | 1933-10-12 | 1934-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1937-04-12 | 1937-10-12 | 1938-04-13 | $7700.00 | Window Closed / Lapsed |