When determining whether you need a federal trademark for your business or product, there are a number of factors to consider. Most importantly, consider what the trademark will actually provide you. If you have a business located in one State, and you have absolutely no plans to operate in additional States, or on-line, a federal trademark may not be as necessary for you.
By simply using your mark in conjunction with goods, you are afforded certain common law trademark rights. Common law trademarks are denoted by a "TM" next to the mark, versus ® next to federally registered trademarks. These rights are limited, and can typically only be enforceable within a limited geographic region where the mark is actually being used. In addition, when suing to enforce common law trademarks, damages may be limited significantly, or barred altogether, and attorney fees usually cannot be recovered. Sometimes, relief is limited to injunctive relief, thus stopping the infringer from infringing.
If you have a product that you sell in multiple States, or online, then a federal trademark should be considered. One of the requirements to obtain a federal trademark is that the mark must be used in interstate commerce. By federally registering your product's mark, you are protecting yourself in all 50 States. If you only had a common law trademark, you may very well be prevented from selling your product in certain locations due to other federally registered or common law trademarks that are being used in other locations.
One interesting concept is the potential for the existence of prior common law trademarks when filing for a federal trademark. You can obtain a federal trademark so long as there are no confusingly similar federally registered trademarks; however, common law trademarks are not considered when obtaining federal registration. This means you can obtain a federal trademark, but you may be barred from using your federal trademark in certain geographic regions if there is a common law trademark that was being used in the limited region prior to the federal registration. You would be able to prevent the common law trademark holder from venturing to new regions though, but you would not be able to stop them from using the prior-used common law trademark.
Federally registering your trademark does offer benefits if there is ever trademark infringement. Should a lawsuit be filed, common law trademark infringement actions are filed under State law, and thus in State Court, while federal trademark infringement actions are filed under federal law, and thus in Federal Court. Federal trademark infringement statutes provide for the recovery of lost profits, statutory damages, court costs and attorney fees, and/or triple damages for willful infringement.
It is important to speak with an attorney when considering the opening of a business, the roll out of a new product, or you have questions regarding your current business or product to see what benefits a federal trademark would offer.