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US2911909A Expired / Lapsed US ⏱️ 0.0 years remaining

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Assignee: EMILY B WILCOX
•
Filing: 1955-10-21
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Granted: 1959-11-10
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Expires: 1975-10-21
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Abstract

No abstract record available.

Inventors

  • 👤 Benjamin H Fuchs

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 09:28
CPC Classifications
E; E21; E21B; E21B31/00; E21B31/107; E21B31/1075; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49815; Y10T29/49822

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US1623475A Cited
US2427377A Cited
US2595615A Cited
US2745345A Cited
US2620029A Cited
US2705920A Cited
US2621895A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1962-11-09 1963-05-11 1963-11-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1966-11-09 1967-05-11 1967-11-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1970-11-09 1971-05-11 1971-11-10 $7700.00 Window Closed / Lapsed

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