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Step by Step Guide
- If you know the PATENT NUMBER, Skip to Step 5 below.
- If you know the PATENTEE OR ASSIGNEE: Check the annual volumes of the Index of Patents for the patent number, then skip to Step 5 below.
- If you know the SUBJECT OF INVENTION:
- Check the Index to the U.S. Patent Classification for the classification number for the subject of the invention.
- Refer to the Manual of Classification to determine the precise classification number for the subject. Where doubt exists as to the choice among several subclasses, consult the Classification Definitions.
- Check the United States Patent Classification-Subclass listing for a list of patent numbers issued in the class and subclass.
- For years after those included in the United States Patent Classification-Subclass listing, check the annual Index of Patents and the weekly issues of the Official Gazette.
- For patent numbers 112, 304-3,778,913, check the Finding List for the volume of the Official Gazette in which that patent number will be found; then locate the volume of the Official Gazette.
- For patent numbers from 3,778,914, find the microfilm reel of the Official Gazette which contains the patent number.
Additional guides for patent and trademark searching: