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US2550820A Expired / Lapsed US ⏱️ 0.0 years remaining

Automatic line testing apparatus, including means for indicating the type of trouble

Assignee: Automatic Electric Laboratories Inc
•
Filing: 1947-10-03
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Granted: 1951-05-01
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Expires: 1967-10-03
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Abstract

No abstract record available.

Inventors

  • 👤 Kessler Frank

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 13:01
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/30

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US1340935A Cited
US1220607A Cited
US1855852A Cited
US1881544A Cited
US2329491A Cited
US2328750A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1954-04-30 1954-10-30 1955-05-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1958-04-30 1958-10-30 1959-05-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1962-04-30 1962-10-30 1963-05-01 $7700.00 Window Closed / Lapsed

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