Under current law, a utility patent lasts for twenty (20) years from the ﬁling date of the earliest application that the patent relates back to, and a design patent lasts for fifteen (15) years from the issue date. Under prior United States law, utility patents lasted for seventeen (17) years from the issue date and design patents lasted for fourteen (14) years from the issue date.
In order to keep a United States utility patent in force, a maintenance fee must be paid at 3-½, 7-½, and 11-½ years after its issuance. Failure to pay these maintenance fees will cause the patent to lapse before its entire term has run. Although the Patent Ofﬁce mails notices of these maintenance fees to the correspondent’s address it has on ﬁle, your patent attorneys should maintain a docket of these payment dates in order to determine whether your company wishes to keep a patent in force.