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US91039A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Improved step-ladder
Assignee: —
•
Filing: —
•
Granted: 1869-06-08
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Expires: 1886-06-08
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:15
CPC Classifications
E; E06; E06C; E06C1/00; E06C1/02; E06C1/32
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) | 1872-06-07 | 1872-12-07 | 1873-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1876-06-07 | 1876-12-07 | 1877-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1880-06-07 | 1880-12-07 | 1881-06-08 | $7700.00 | Window Closed / Lapsed |