How do I enforce my trademark rights?
While trademark owners have a variety of rights, the chief right is the ability to prevent others from using confusingly similar marks (what is known as trademark infringement). To have such enforceable rights, however, a trademark owner must be actively using their trademark. So the first step to enforcing your trademark rights is to keep actively using your mark. In addition, while it is not necessary to include a trademark notice when you use your trademarks, it is a good idea to do so anyway.
While you are using the mark, you should observe the market for any use of marks that are the same as, or similar to, your trademark. In addition, you should track applications for trademark registrations, in case others are seeking to register your mark or a mark confusingly similar to your mark. This process is known as “policing” your trademark.
If you find someone using your mark, or using something that is infringing your trademark rights, you should consult a trademark attorney. However, the basic steps in enforcing your rights would be the same regardless of whether or not you consult a trademark attorney. You should begin by conducting a trademark search to determine whether the infringing mark actually has superior rights to your mark (for example, if it was federally registered on the Principal Register before your mark, its owner may have stronger rights than you, and you could even be the one actually committing trademark infringement). If you determine that your trademark has superior rights to the infringing mark, you should send a cease and desist letter demanding that the other person stop using their mark because it is infringing your rights.
If the infringing party agrees to stop using the mark, that should be the end of the matter, unless you believe that their infringing use has already caused you substantial damage. In that case, or in the event that the infringing party does not agree to stop using the mark, you can file a lawsuit against them for trademark infringement. If your trademark is federally registered, you can sue them in federal court - otherwise, you must sue them in state court (unless your lawsuit meets one of the other standards for being brought in federal court). In a lawsuit for trademark infringement, you can seek injunctive relief, where you are asking the court to order the other side to stop using the mark. You also may be able to seek money damages (such as the other side’s profits or your lost profits) depending on the specific circumstances of your case.