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US2826638A Expired / Lapsed US ⏱️ 0.0 years remaining

Signaling system

Assignee: AT&T Inc
•
Filing: 1952-04-26
•
Granted: 1958-03-11
•
Expires: 1972-04-26
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Abstract

No abstract record available.

Inventors

  • 👤 Wayne V K Large
  • 👤 Robert O Soffel
  • 👤 Bernard J Yokelson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 02:43
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/444; H04Q1/45; H04Q1/453; H04Q3/00; H04Q3/42

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US2282271A Cited
US2250100A Cited
US2535102A Cited
US2519763A Cited
US2666809A Cited
US2654002A Cited
US2630525A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1961-03-10 1961-09-09 1962-03-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-03-10 1965-09-09 1966-03-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-03-10 1969-09-09 1970-03-11 $7700.00 Window Closed / Lapsed

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