Patents by Inventor Yuichi Koganezawa

Yuichi Koganezawa 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).

  • Electronic signature addition method, electronic signature verification method, and system and computer program product using these methods
    Patent number: 5915024
    Abstract: An apparatus for adding an electronic signature to document data includes a delimiter character detector for dividing the input document data into a plurality of divided document data by using as a delimiter a predetermined character appearing in a document represented by the document data, a digest generator and an encrypter for generating an electronic signature based on the divided document data for each divided document data, and a signature-added message generator for generating the divided document data, the electronic signature based on the divided document data, and information for associating the divided document data with the electronic signature.
    Type: Grant
    Filed: June 17, 1997
    Date of Patent: June 22, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shoji Kitaori, Yuichi Koganezawa