A. Unfortunately, you can’t search the US Patent and Trademark Office (USPTO) database <www.uspto.gov/patft> for the names of patent holders prior to 1976. To find your ancestor in that database, you need to know the patent number or the current US patent classification number.
You still can learn about your ancestor’s invention if you have his full name and can guess the year he applied for a patent, according to researcher Nick D’Alto. First, see <www.uspto.gov/web/offices/ac/ido/ptdl> to find a nearby Patent and Trademark Depository Library (PTDL) — part of a network of libraries that hold USPTO materials. At the PTDL, look for your ancestor in the microfiche Index of Patents Issued From the United States Patent and Trademark Office, Part I: Patentee/Assignee Index. This annual alphabetical index lists inventors and their patents.
Once you find a patent number, you’ll be able to search for his patent on the USPTO Web site. But while you’re at a PTDL, go ahead and look up the patent number in the Official Gazette of the United States Patent and Trademark Office to find the abstract describing your ancestor’s invention.