Patents by Inventor Siegfried Keil

Siegfried Keil 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).

  • Writing instrument
    Patent number: D437888
    Type: Grant
    Filed: January 23, 1998
    Date of Patent: February 20, 2001
    Assignee: Merz & Krell GmbH & Co.
    Inventors: Hariolf Briggl, Siegfried Keil
  • Writing instrument
    Patent number: D443896
    Type: Grant
    Filed: August 12, 1999
    Date of Patent: June 19, 2001
    Assignee: Merz & Krell GmbH & Co.
    Inventors: Hariolf Briggl, Siegfried Keil
  • Writing instrument
    Patent number: D567288
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: April 22, 2008
    Assignee: Merz & Krell GmbH & Co., KGaA
    Inventor: Siegfried Keil
  • Writing utensil
    Patent number: D485574
    Type: Grant
    Filed: December 5, 2000
    Date of Patent: January 20, 2004
    Assignee: Merz & Krell GmbH & Co KGaA
    Inventor: Siegfried Keil