A trademark is infringed by any person who, without permission, uses any reproduction, counterfeit, copy, or colorable imitation of a trademark; or uses a trademark likely to cause confusion, or to cause mistake, or to deceive as to the source of the goods and/or services, or to falsely create an association with the owner of mark, or approval by the owner of the mark; or uses a trademark that causes the dilution of a famous trademark. On the other hand, a trademark is not infringed by the fair use of that trademark in comparative commercial advertising or promotion to identify competing goods or services, or the noncommercial use of a trademark, or in any form of news reporting or news commentary.
If your trademark is being infringed, you need to tell the infringer to stop (typically by sending a “cease and desist” letter). If that doesn’t work and infringement persists, you should bring a lawsuit against the infringer. The lawsuit could be brought in state court or, if you qualify (because of use of your trademark in “commerce” as that term is defined under federal law), in federal court.
You will need to prove at trial that you own the trademark (if you have a registration, that proof may be automatic) and that infringement has occurred. The legal standard is not actual confusion, but rather only the likelihood of confusion due to the infringement. This may require the use of expert witnesses, if the infringing trademark is not exactly the same as your trademark, or if the infringing goods and/or services are not exactly the same as your goods and/or services.
The remedies you could seek in a lawsuit depend on the circumstances. You could ask for an injunction against the use of the infringing trademark. You could ask for an injunction against the manufacture, use, display, or sale of goods and/or services under the infringing mark. You could ask for the destruction of goods sold under the infringing. You could request that you be awarded actual damages, which could be measured as the profits you lost due to the infringement or the profits the infringer gained due to the infringement. You could ask for these damages to be multiplied if there was intentional bad faith in the infringement. Alternatively, if the lawsuit was brought under federal law, you could ask for statutory damages, which can range from $1,000 to $200,000 per trademark, or up to $2,000,000 per trademark for willful use. If the lawsuit is brought in state court, the amount of statutory damages will vary, state by state, though it is typically capped at a much lower rate than the federal range. Finally, in certain cases, you can also recover your attorney’s fees incurred in bringing the lawsuit, as well as court costs.
It is also possible to avoid a lawsuit and reach a settlement with the infringer. You could ask for any or all of the remedies that are available through a lawsuit. If the parties can reach a settlement, the infringement is likely to be resolved much quicker and at far less expense than if a lawsuit was undertaken.