US203900A
Expired / Lapsed
US
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Improvement in drive-well-point filters
Assignee: —
•
Filing: —
•
Granted: 1878-05-21
•
Expires: 1895-05-21
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:32
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/02; E21B43/08; E21B43/086; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/496; Y10T29/49604
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) | 1881-05-20 | 1881-11-19 | 1882-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1885-05-20 | 1885-11-19 | 1886-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1889-05-20 | 1889-11-19 | 1890-05-21 | $7700.00 | Window Closed / Lapsed |