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US1720700A Expired / Lapsed US ⏱️ 0.0 years remaining

Core drill

Assignee: DOHENY STONE DRILL CO
•
Filing: 1924-08-19
•
Granted: 1929-07-16
•
Expires: 1944-08-19
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Abstract

No abstract record available.

Inventors

  • 👤 Stone Frederick

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 05:34
CPC Classifications
E; E21; E21B; E21B25/00; E21B25/10; E21B25/12

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1932-07-15 1933-01-14 1933-07-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1936-07-15 1937-01-14 1937-07-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1940-07-15 1941-01-14 1941-07-16 $7700.00 Window Closed / Lapsed

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