I've Been Sued . . .

How does a trademark infringement lawsuit begin?

A trademark lawsuit begins when the trademark owner files a complaint with a court alleging trademark infringement. Among other things, the complaint names the parties involved and sets forth the allegations that form the basis of the lawsuit. Trademark owners who decide to sue may file their complaint in either state court or federal court, depending on the circumstances. However, in most cases, the trademark owner, as plaintiff, will choose federal court. Even when a plaintiff chooses state court, it may be possible for the defendant to have the case "removed" to federal court.

Frequently, either before or at the time a complaint is filed, the trademark owner or the owner's U.S.-licensed attorney may send you a letter/email or otherwise contact you to make claims about the owner's trademark rights and demand that you take certain actions, such as ceasing use of your mark.

What are my options to respond to the suit?

Your duty to respond to a complaint is triggered when the plaintiff formally "serves" the complaint on you, along with a "summons," which is a court notice requiring you to appear before the court and respond to the complaint by a certain date. If you are sued, you must formally respond to the complaint, either by filing a document called an "answer" with the court, or by filing a motion based on one of the grounds set forth in Rule 12 of the Federal Rules of Civil Procedure, if any apply. You must file the answer or any applicable Rule 12 motion within the time period set by the court's rules and serve a copy on the plaintiff. If you fail to timely file an appropriate response to the complaint, the court may enter a default judgment against you and order you to pay damages or perform other remedial actions.

These are only the first steps of a litigation process that can be very complicated. If you are sued for trademark infringement, a U.S.-licensed attorney experienced in trademark litigation can assist you in deciding the best course of action, which may include one or more of the following options:

  • Challenging the claimed trademark;
  • Denying that the trademark owner has proved infringement;
  • Asserting a defense to the alleged infringement; and/or
  • Negotiating a settlement of the lawsuit by, for example, agreeing to take certain actions to avoid likelihood of confusion.

When considering options, keep in mind that litigation is usually expensive and time-consuming, and it can take years before a court delivers a decision. And, even when a court reaches a decision, it may be appealed to higher courts, resulting in additional time and expense.

How do I find a lawyer?

The state bar association where you or your business is located and the various national bar associations have directories of U.S.-licensed attorneys. Look for an attorney who specializes in trademark litigation. For more information on local assistance, please visit the USPTO locations page and the access our free services page

How do I know whether I'm infringing?

To support a trademark infringement claim in court, a plaintiff must prove that it owns a valid mark, that it has priority (its rights in the mark(s) are "senior" to the defendant's), and that the defendant's mark is likely to cause confusion in the minds of consumers about the source or sponsorship of the goods or services offered under the parties' marks. When a plaintiff owns a federal trademark registration on the Principal Register, there is a legal presumption of the validity and ownership of the mark as well as of the exclusive right to use the mark nationwide on or in connection with the goods or services listed in the registration. These presumptions may be rebutted in the court proceedings.

Generally, the court will consider evidence addressing various factors to determine whether there is a likelihood of confusion among consumers. The key factors considered in most cases are the degree of similarity between the marks at issue and whether the parties' goods and/or services are sufficiently related that consumers are likely to assume (mistakenly) that they come from a common source. Other factors that courts typically consider include how and where the parties' goods or services are advertised, marketed, and sold; the purchasing conditions; the range of prospective purchasers of the goods or services; whether there is any evidence of actual confusion caused by the allegedly infringing mark; the defendant's intent in adopting its mark; and the strength of the plaintiff's mark.

The particular factors considered in a likelihood-of-confusion determination, as well as the weighing of those factors, vary from case to case. And the amount and quality of the evidence involved can have a significant impact on the outcome of an infringement lawsuit.

In addition to claiming likelihood of confusion, a trademark owner may claim trademark "dilution," asserting that it owns a famous mark and the use of your mark diminishes the strength or value of the trademark owner's mark by "blurring" the mark's distinctiveness or "tarnishing" the mark's image by connecting it to something distasteful or objectionable-even if there is no likelihood of confusion.

An experienced U.S.-licensed trademark attorney, taking the particular circumstances of your case into consideration, should be able to provide you with an opinion as to the validity and strength of a trademark owner's claims.

How can I use USPTO records to find out more information about the claimed trademark and who owns it?

You can search our trademark database for similar trademarks. If you know the application serial number or registration number for the particular mark, you may use the Trademark Status and Document Retrieval (TSDR) system to view/download relevant application and registration records.

How can I challenge a trademark registration or application?

Several options exist to challenge another party's trademark registration or application, depending on the particular circumstances and grounds for challenging:

  • You may challenge a trademark registration issued by the USPTO by filing a petition to cancel the registration with the Trademark Trial & Appeal Board (TTAB).
  • You may challenge an application for trademark registration at the USPTO by filing an opposition with the TTAB within 30 days after it is published in the Official Gazette.
  • You may file a declaratory judgment lawsuit, asking a court to declare that your mark does not infringe the trademark owner's mark, and/or that the trademark owner's mark is invalid.
  • If you are already a defendant in an infringement lawsuit, you may assert an "affirmative defense" and/or a counterclaim against the plaintiff challenging the validity of the plaintiff's trademark.

Again, a U.S.-licensed attorney with trademark expertise can help advise you about the various options available to challenge trademark registrations and applications. Read the Do I need an attorney?" page for further information.


Black's Law Dictionary (9th ed. 2009)

Federal Rules of Civil Procedure (2013)

McCarthy on Trademarks & Unfair Competition (5th ed. 2017 updated quarterly)​

Trademark Manual of Examining Procedure (Oct. 2014)

Trademark Trial & Appeal Board Manual of Procedure (June 2013)

The information presented on this site does not constitute legal advice. It should not be considered a substitute for advice from a U.S.-licensed attorney. Reference to any specific organizations, attorneys, law firms, corporations, or websites does not constitute the USPTO's endorsement or recommendation.

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