Patent US3257138A successfully refreshed from Google Patents.
Patent US2531577A successfully refreshed from Google Patents.
US2531577A
Expired / Lapsed
US
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Rail fastener
Assignee: Individual
•
Filing: 1945-03-05
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Granted: 1950-11-28
•
Expires: 1965-03-05
Abstract
No abstract record available.
Inventors
- 👤 John A Mcgrew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:54
CPC Classifications
E; E01; E01B; E01B9/00; E01B9/38; E01B9/44; E01B9/46; E01B9/48; E01B9/486
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1886265A
Cited
US1887457A
Cited
US2056632A
Cited
US2203624A
Cited
US2168676A
Cited
US2127130A
Cited
US2210334A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-11-27 | 1954-05-29 | 1954-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-27 | 1958-05-29 | 1958-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-27 | 1962-05-29 | 1962-11-28 | $7700.00 | Window Closed / Lapsed |