Patents by Inventor Silvia Davidson

Silvia Davidson 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).

  • Mathematical aid
    Patent number: D317787
    Type: Grant
    Filed: February 21, 1990
    Date of Patent: June 25, 1991
    Inventors: William A. Davidson, Silvia Davidson, John D. Charters