Registration Renewal and Grace Period
Your trademark registration is good for ten years from your completed application date: the date you filed the application and paid the registration fee. You may renew your registration nine years after the application date or within six months after your registration lapses. The U.S. Trademark Act gives you a six-month grace period to renew the registration after your original registration ends. If you renew during the grace period, you'll have to pay extra fees. You'll need to complete and file an Application for Renewal and an affidavit of use with the U.S. Patent and Trademark Office. An affidavit of use is a sworn statement that declares the mark is still in use and describes the mark's commercial uses.
If you've let your trademark registration lapse and didn't renew the mark during the grace period, you must go through the registration process again. The trademark application is treated as a new application. Your trademark is subject to the same examination by the U.S. Patent and Trademark Office it went through during your original registration. The trademark examiner doesn't have to accept your trademark for registration even if it was registered before.
If you don't renew your registration, another party might try to use your trademark. Registration isn't necessary for trademark protection, according to the Berkman Center for Internet & Society at Harvard University, so you may not lose the right to use the mark. You will lose some protection, however, such as the right to sue a third party for using your mark without permission in federal court. You won't have the right to receive damages and court costs from a lawsuit for misuse of your mark without a valid registration.
The U.S. Patent Act does allow you to have your lapsed trademark registration reinstated, without going through the application process again, if the U.S. Patent and Trademark Office is at fault for the lapse. You still must have filed the necessary renewal documents by the end of your grace period. If the office failed to process the documents or lost the papers, you may apply for reinstatement. You must file a request for reinstatement with the U.S. Patent and Trademark Office within two months of receiving the registration lapse notice.