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US2851657A Expired / Lapsed US ⏱️ 0.0 years remaining

Comparison type electrical test set

Assignee: AT&T Inc
•
Filing: 1955-02-04
•
Granted: 1958-09-09
•
Expires: 1975-02-04
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Abstract

No abstract record available.

Inventors

  • 👤 Robert K Smith

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 10:44
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

BE515398A Cited
US383605A Cited
US610903A Cited
US1333892A Cited
US1347772A Cited
US1901488A Cited
US2468398A Cited
US2547011A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1961-09-08 1962-03-10 1962-09-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-09-08 1966-03-10 1966-09-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-09-08 1970-03-10 1970-09-09 $7700.00 Window Closed / Lapsed

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