Patent Yard Sign in
Expired, full termArchiveSolo inventor

Telephone system

US 2,258,980 A · Inventors: EAGON LLOYD L et al.

USPTO PDF

Overview

The published document from the USPTO: abstract, claims, description and drawings. Open it full size

Read the whole patent

Listed from its USPTO record in Patent Yard's full-term archive. Its claims, description and drawings are in the USPTO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted October 14, 1941. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by October 14, 1958.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledApril 18, 1940
GrantedOctober 14, 1941
Term endedOctober 14, 1958
Application number—
Classification (CPC)H04M3/12
Length11 pages

Timeline

Timeline From USPTO dates

194119431945194719491951195319551957Application filedApril 18, 1940Patent grantedOct 14, 1941Term endedOct 14, 1958

Sources & verification