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US2580911A Expired / Lapsed US ⏱️ 0.0 years remaining

Foundation structure for derricks

Assignee: Individual
•
Filing: 1947-05-27
•
Granted: 1952-01-01
•
Expires: 1967-05-27
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Abstract

No abstract record available.

Inventors

  • 👤 Michael S Lobenthal
  • 👤 Florence B Downs

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:29
CPC Classifications
E; E02; E02B; E02B17/00; E02B17/02

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US1681533A Cited
US2210408A Cited
US2248051A Cited
US2422168A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1954-12-31 1955-07-02 1956-01-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1958-12-31 1959-07-02 1960-01-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1962-12-31 1963-07-02 1964-01-01 $7700.00 Window Closed / Lapsed

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