How do I obtain the status of a patent?

The Patent Application Information Retrieval (PAIR) system permits third parties to obtain information about applications that have been published pursuant to 35 U.S.C. 122(b) and issued patents, such as the status of maintenance fee payments and whether or not a reissue application or reexamination request has been filed. PAIR can be accessed on the United States Patent and Trademark Office (USPTO) web site at   For information about whether or not a specific patent has been litigated, it is best that you search a legal database.  Information on pending patent applications will not be given over the telephone to anyone who is not the inventor or his/her legal representative.

If you require further assistance or do not know the number of the patent, please call the Official Search Unit. The number is (703) 308-2733 .

USPTO FAQ - Questions and Answers (15JUN2006)