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US2990811A Expired / Lapsed US ⏱️ 0.0 years remaining

Marking chalk sharpener

Assignee: Individual
•
Filing: 1960-05-31
•
Granted: 1961-07-04
•
Expires: 1980-05-31
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Abstract

No abstract record available.

Inventors

  • 👤 Mackie William

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 10:42
CPC Classifications
B; B43; B43L; B43L23/00; Y; Y10; Y10T; Y10T83/00; Y10T83/222; Y10T83/869; Y10T83/8773; Y10T83/8798; Y10T83/8812; Y10T83/8815

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US1292181A Cited
US2185985A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1964-07-03 1965-01-02 1965-07-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1968-07-03 1969-01-02 1969-07-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1972-07-03 1973-01-02 1973-07-04 $7700.00 Window Closed / Lapsed

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