Patent US3721828A successfully refreshed from Google Patents.
Patent US271838A successfully refreshed from Google Patents.
US271838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microscopic photographic transparency
Assignee: —
•
Filing: —
•
Granted: 1883-02-06
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Expires: 1900-02-06
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:14
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/02; G02B27/022; G02B27/024; G02B27/025
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) | 1886-02-05 | 1886-08-07 | 1887-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1890-02-05 | 1890-08-07 | 1891-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1894-02-05 | 1894-08-07 | 1895-02-06 | $7700.00 | Window Closed / Lapsed |