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US2201296A Expired / Lapsed US ⏱️ 0.0 years remaining

Telephone system

Assignee: AT&T Inc
•
Filing: 1938-10-18
•
Granted: 1940-05-21
•
Expires: 1958-10-18
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Abstract

No abstract record available.

Inventors

  • 👤 Alexis A Lundstrom
  • 👤 Edward L Norton

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 04:49
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/42; H04M; H04M1/00; H04M1/26; H04M1/30; H04M1/50; H04Q5/00; H04Q5/02; H04Q5/08

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1943-05-21 1943-11-20 1944-05-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1947-05-21 1947-11-20 1948-05-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1951-05-21 1951-11-20 1952-05-21 $7700.00 Window Closed / Lapsed

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