Registering a trademark increases the protection it receives, helps stop others from using your trademark, and increases the remedies should someone infringe upon the trademark. A. To Obtain Priority
In the USA, filing an application for trademark registration is, by law, equivalent to actual use of the trademark nationwide for purposes of priority. The trademark owner receives the presumption of being the valid owner of the mark. So, by filing you can potentially put yourself in a position to stop anyone who later adopts the same trademark, if the trademark itself is protectable. The United States Patent and Trademark Office ("USPTO") will refuse registration to any trademarks it deems confusingly similar to your Registered trademark.
B. To Give It Much Greater Protection, Automatically
Since a US trademark registration is issued pursuant to Federal law, the trademark owner gets an automatic right to sue in Federal court for any violation of the trademark.The trademark owner, upon registration, obtains the valuable right to put a registration symbol after the mark, alerting others to your registration and preventing the defense of innocent infringement, and entitling you to or greater damage in some cases. Registration grants the trademark owner the right to recover up to triple damages and attorney's fees from an infringer by eliminating the defense of innocent infringement when the infringer knows of the registration and has no good defense. The trademark will appear in trademark search reports ordered by others, likely discouraging others from proceeding with the registration of the same or similar mark. A registration increases the likelihood of the successful filing of a complaint under the UDRP (uniform dispute resolution policy) against an infringing Internet domain name.
C. Obtain International Recognition
Most foreign countries do not respect trademark rights established solely through use, unless the trademark becomes famous enough to be considered known as a trademark in that country, so without a registration you may be powerless to stop foreign use of your trademark. A United States Trademark Registration can be used as a basis for obtaining registration of your trademark in foreign countries. The filing of a trademark application with the United States Patent and Trademark Office allows you to take advantage of treaties between the USA and every other major country. Those treaties give recognition to an American trademark by those countries, since those countries want their trademarks respected in the USA.
C. To Put Others on Notice of Your Rights
Registration provides official notice to others that a trademark is already taken; consequently, a company that later adopts a confusingly similar trademark cannot legally claim ignorance of the mark, since US law charges every person with knowledge of every registered trademark and places a duty on every person to avoid likelihood of confusion between any registered trademark and that person's trademark.
D. To Make Your Trademark "Incontestable" The trademark owner obtains the future right to make the mark "incontestable," which provides conclusive evidence regarding the validity of the mark and of the registrant's exclusive right to use the mark, subject to only a very few limited exceptions. If you have to go into court and protect your trademark against an infringer, this is a well-respected right that will make your case much less expensive and much easier to pursue.