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US2507566A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrical testing apparatus

Assignee: AT&T Inc
•
Filing: 1948-08-30
•
Granted: 1950-05-16
•
Expires: 1968-08-30
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Abstract

No abstract record available.

Inventors

  • 👤 Stewart E Frisbie
  • 👤 Gilbert E Weeks

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 05:46
CPC Classifications
G; G01; G01R; G01R27/00; G01R27/02; G01R27/26; G01R27/2617; G01R27/2623; G01R27/2629

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US1983388A Cited
US2153990A Cited
US2363577A Cited
US2417488A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1953-05-15 1953-11-14 1954-05-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1957-05-15 1957-11-14 1958-05-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1961-05-15 1961-11-14 1962-05-16 $7700.00 Window Closed / Lapsed

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