Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Standard Elektrizitaetas Gesellschaft AG
AT&T Inc
Original Assignee
Standard Elektrizitaetas Gesellschaft AG
Bell Telephone Laboratories Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US729735Aexternal-prioritypatent/US2159020A/en
Application filed by Standard Elektrizitaetas Gesellschaft AG, Bell Telephone Laboratories IncfiledCriticalStandard Elektrizitaetas Gesellschaft AG
Application grantedgrantedCritical
Publication of DE698644CpublicationCriticalpatent/DE698644C/de