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US3188401A Expired / Lapsed US ⏱️ 0.0 years remaining

Selective service observing circuit

Assignee: AT&T Inc
•
Filing: 1961-11-15
•
Granted: 1965-06-08
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Expires: 1981-11-15
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Abstract

No abstract record available.

Inventors

  • 👤 William G Barrett
  • 👤 George E Koch

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 08:39
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/22; H04M3/36

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 129 words
IN A TELEPHONE SYSTEM INCLUDING A PLURALITY OF ATTENDANT-CONTROLLED PRIVATE BRANCH EXCHANGES EACH ASSOCIATED WITH A RESPECTIVE ONE OF A PLURALITY OF TRUNKS, A SERVICE OBSERVING CIRCUIT COMPRISING MEANS FOR STORING A PLURALITY OF NUMERICAL INDICATIONS EACH CORRESPONDING TO THE CALLING NUMBER OF A RESPECTIVE ONE OF SAID PRIVATE BRANCH EXCHANGES, MEANS RESPONSIVE TO DIAL PULSES ON ANY ONE OF SAID TRUNKS FOR COMPARING THE NUMBERS CORRESPONDING ING TO SAID DIAL PULSES WITH THE NUMBERS CORRESPONDING TO SAID INDICATIONS, AND MEANS RESPONSIVE ONLY TO A MATCH BETWEEN A STORED ONE OF SAID NUMERICAL INDICATIONS AND A NUMBER CORRESPONDING TO SAID DIAL PULSES AS DETERMINED BY SAID COMPARING MEANS FOR GENERATING A SERVICE OBSERVING ALERTING SIGNAL, WHEREBY SERVICE OBSERVING MAY BE RESTRICTED TO CALLS MADE TO SAID PRIVATE BRANCH EXCHANGE
Claim 2
Dependent Claim 129 words
IN A TELEPHONE SYSTEM INCLUDING A PLURALITY OF ATTENDANT-CONTROLLED PRIVATE BRANCH EXCHANGES EACH ASSOCIATED WITH A RESPECTIVE ONE OF A PLURALITY OF TRUNKS, A SERVICE OBSERVING CIRCUIT COMPRISING MEANS FOR STORING A PLURALITY OF NUMERICAL INDICATIONS EACH CORRESPONDING TO THE CALLING NUMBER OF A RESPECTIVE ONE OF SAID PRIVATE BRANCH EXCHANGES, MEANS RESPONSIVE TO DIAL PULSES ON ANY ONE OF SAID TRUNKS FOR COMPARING THE NUMBERS CORRESPONDING ING TO SAID DIAL PULSES WITH THE NUMBERS CORRESPONDING TO SAID INDICATIONS, AND MEANS RESPONSIVE ONLY TO A MATCH BETWEEN A STORED ONE OF SAID NUMERICAL INDICATIONS AND A NUMBER CORRESPONDING TO SAID DIAL PULSES AS DETERMINED BY SAID COMPARING MEANS FOR GENERATING A SERVICE OBSERVING ALERTING SIGNAL, WHEREBY SERVICE OBSERVING MAY BE RESTRICTED TO CALLS MADE TO SAID PRIVATE BRANCH EXCHANGE

References Cited (Backward Citations)

US1350975A Cited
US1691554A Cited
US2709722A Cited
US2875286A Cited
US2913526A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1968-06-07 1968-12-07 1969-06-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1972-06-07 1972-12-07 1973-06-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1976-06-07 1976-12-07 1977-06-08 $7700.00 Window Closed / Lapsed

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