How to Research a
U S. Patent Number Online
If you have the number of a U.S. patent and would
like to see the patent drawings or read the patent text, you can do it online.
The U.S. Patent and Trademark Office (USPTO) has a website where this
information is available, and you can examine copies of documents that used to
be available only in Washington or at a few large regional libraries.
The address is: http://www.uspto.gov
While there are shortcuts into the system, if you
start at this homepage, you may get a better idea of what other information
you can find here.
1. Click "Patents"
2. Under "Services",
click "eSearch Patents"
3. Click "Patent
4. Type your patent
number in the query box - commas are not necessary, but if your patent number
begins with the letter "D", indicating a design patent, include the "D" - then
click on "Search"
5. Click on the patent
number (now colored "blue") in the lower left corner of the page
6. Click on "Images"
You are now at page one of your patent, and you
can navigate through the pages of the patent using the tools on the left side
of the page. Patents for inventions (or, or as USPTO calls them, Utility
patents) are usually at least two pages, with the first page showing patent
drawings and subsequent pages stating the Specifications and Claims.
Design patents are usually just one page.
If you go back to step 6, you will see the Current
U. S. Class number (CCL) for your patent. This information is useful if
you want to search for items in the same classification, i.e. other "match
safe", "snuff box" or "spoon" patents. Since some patents will have
multiple classification numbers, you can widen your net by searching with
these numbers. You can also obtain classification numbers at "Tools to
Help in Searching by Patent Classification" at step 3.
Once you have a classification number and want to
search for other items in that particular class, click on "Advanced Search"
(at step 3) or "Advanced" (at steps 4 - 6). Then,
a. In the query box, type
in the class in this format: ccl/[the class number]/[the subclass
number]. For example, "ccl/206/134."
b. Specify a range
of years in the "Select Years" box.
c. Click on
You now have a list of patents of a particular
class for the range of years you have specified, and they will be in
chronological order based on the date of the Tuesday of the week in which the
patent was granted. From here, you can access an individual patent file
by following steps 5 & 6 above.
Unfortunately for those interested in historical
research, pre-1976 patents are only searchable by patent number or
classification. If you only have a pre-1976 patent date, you also may be
able to find the patent if you can hit upon the correct class for the item
(see "Tools to Help..." above) and track the patent down, hit and miss.
You cannot "Advanced Search" by date or inventor's name, etc. as you can with
post-1975 patents, so that searching for patents by an inventor named Edison
before 1976 will give you "0" hits.
Other Research Links
U.S. Patent Dating Chart
English Registry Marks
of American Silver Marks