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US2425549A Expired / Lapsed US ⏱️ 0.0 years remaining

Calculation checking device

Assignee: International Business Machines Corp
•
Filing: 1944-08-31
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Granted: 1947-08-12
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Expires: 1964-08-31
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Abstract

No abstract record available.

Inventors

  • 👤 Hans P Luhn

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 03:45
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/08; G06F11/10; G06F11/1008; G06F11/1012; G06F11/104

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US719734A Cited
US1283293A Cited
US2241591A Cited
US2350499A Cited
US2364540A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1950-08-11 1951-02-10 1951-08-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1954-08-11 1955-02-10 1955-08-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1958-08-11 1959-02-10 1959-08-12 $7700.00 Window Closed / Lapsed

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