Patents by Inventor Leif Lanning

Leif Lanning has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • System for securing access to equipment connectable to a telephone communication channel
    Patent number: 5469499
    Abstract: A system for accessing equipment connectable to a secured telephone communication channel by sensing ringing current on an access telephone communication channel. Ringing current on the secured channel is controlled such that the secured channel does not answer unless the access channel was called within a preset time period prior to calling the secured channel.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: November 21, 1995
    Inventor: Leif Lanning