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US3525237A Expired / Lapsed US ⏱️ 0.0 years remaining

Drill-stem

Assignee: MINISTERUL PETROLULUI
•
Filing: 1968-06-18
•
Granted: 1970-08-25
•
Expires: 1988-06-18
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Abstract

No abstract record available.

Inventors

  • 👤 Ioan Lari

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 19:07
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/16

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

BE564188A Cited
DE206517C Cited
US2263579A Cited
US2330564A Cited
US3067593A Cited
US3338069A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1973-08-24 1974-02-23 1974-08-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1977-08-24 1978-02-23 1978-08-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1981-08-24 1982-02-23 1982-08-25 $7700.00 Window Closed / Lapsed

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