Patent US2470113A successfully refreshed from Google Patents.
Patent US3890431A successfully refreshed from Google Patents.
US53931A
Expired / Lapsed
US
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Improvement in artificial legs
Assignee: —
•
Filing: 1866-04-10
•
Granted: 1866-04-10
•
Expires: 1886-04-10
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:20
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/50; A61F2/60; A61F2/66; A61F2/6607; A61F2002/5007; A61F2002/5009; A61F2002/5016; A61F2002/502; Y; Y10; Y10T; Y10T403/00; Y10T403/32; Y10T403/32975
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) | 1869-04-09 | 1869-10-09 | 1870-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1873-04-09 | 1873-10-09 | 1874-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1877-04-09 | 1877-10-09 | 1878-04-10 | $7700.00 | Window Closed / Lapsed |