Likelihood of Confusion: How Do You Determine If a Trademark is Infringing?

Are you concerned that a competitor is unfairly using the same or a similar trademark as your business? If you believe someone else is using a mark that's too similar to yours, you can stop them by claiming that the use of their mark infringes on your trademark rights.

To prove trademark infringement, you must apply the "likelihood of confusion standard." Put simply, you must prove that consumers would likely be confused about the source of your goods or services if both your mark and the allegedly infringing mark exist.

What Is Trademark Infringement?

"Trademark infringement" is when someone uses a mark that's the same as or similar to yours in a way that could likely cause confusion among consumers. Specifically, consumers are confused about the source of a set of goods or services.

For example, suppose you use the name "Flying Machine Bikes" for your bicycle shop. You find out that a nearby bike shop has just started using "The Flying Machine Bike Shop" for their business. Some consumers might confuse the two shops. They might either believe that they're affiliated with each other in some way or be unsure which shop provided the purchased goods and services. In other words, consumers would be confused about the source or provider of the connected goods or services.

To stop trademark infringement, you must prove both of the following:

1. You're the senior user: You started using your mark before the alleged infringer started using their mark, and
2. Likelihood of confusion: Consumers would be confused about the source (provider) of the two marks.

If you can successfully prove these two points, then you can force the other user to stop using their confusing mark. If they continue to use the infringing mark, then you can recover money damages.

When Do You Need to Prove a Likelihood of Confusion?

Typically, issues of likelihood of confusion come up during the trademark registration process or when one company becomes aware of another company's trademark use in the real world.

During the Review of a Trademark Application

When you submit your trademark application to the U.S. Patent and Trademark Office (USPTO), your application will be assigned to a trademark examiner for review. The trademark examiner will review your application to make sure that your application includes all the required information and that your mark is registrable.

To make sure that your mark is registrable, the examiner will run a search of all the trademarks currently in the USPTO database, including registered and applied-for marks. If the examiner identifies any marks that they think are confusingly similar to yours, then they'll refuse to register your mark. Specifically, the examiner will issue an office action that tells you that your mark can't register because of a likelihood of confusion with a preexisting mark. You'll need to overcome the likelihood of confusion refusal if you want your application to move forward toward registration.

If you've already applied for or registered your mark, then your mark will also be part of the USPTO database. So, anyone trying to register a confusingly similar mark will, in theory, face the same likelihood of confusion refusal.

When a Trademark Owner Discovers the Confusingly Similar Mark

When you own a trademark, you might become aware that someone else is using a potentially confusing mark. You might make this discovery when the other party either:

• tries to register the trademark, or
• uses the mark in the marketplace.

If someone tries to register a confusingly similar mark to yours, then your job might be a little easier. You can let the examiner assert your trademark rights on your behalf. In other words, you can let the examiner make the likelihood of confusion argument for you.

But if the examiner happens to not flag your mark or the applicant overcomes the likelihood of confusion refusal, it's not over for you. You can oppose the mark's registration later in the application process before the mark registers. If the mark is already registered but you started using your mark first, then you can also petition to cancel the registration.

If the mark isn't registered and you come across the mark outside the USPTO registration process, then you can contact the trademark user to try to stop the trademark infringement. You can send the user a cease-and-desist letter (sometimes called a "demand letter"). The cease-and-desist letter should:

• inform them your rights in the trademark
• explain that you believe the use of their mark could confuse consumers
• demand that they stop using their mark and don't use it in the future, and
• cover what will happen if they don't stop using the mark (for example, you'll file a lawsuit).

If they don't respond to the cease-and-desist letter or refuse to stop using the mark, then you might have to file a trademark infringement lawsuit. In court, you'll need to prove that the other party's use of the mark creates a likelihood of confusion with your trademark. You'll probably also want to hire a trademark lawyer to help you with your infringement case.

Determining Likelihood of Confusion: The Polaroid Factors

When determining likelihood of confusion, courts use several factors derived from a 1961 case. (Polaroid Corp. v. Polarad Elecs. Corp., 287 F.2d 492 (2d Cir. 1961).) These factors, sometimes known as the "Polaroid factors," can vary slightly as federal courts apply them throughout the country. The factors are intended as a guide, and not all factors are particularly helpful in any given case.

Many courts apply the Polaroid factors to determine whether a likelihood of confusion exists between two marks:

• Strength of the senior user's mark. The stronger or more distinctive the senior user's mark, the more likely the confusion.
• Similarity of the marks. The more similarity between the two marks themselves, the more likely the confusion.
• Similarity of the products or services. The more that the senior and junior user's goods or services are related, the more likely the confusion.
• Likelihood that the senior user will bridge the gap. If it's probable that the senior user will expand into the junior user's product area, the more likely there will be confusion.
• Evidence of actual confusion. Proof of consumer confusion isn't required. But when the trademark owner can show that the average reasonably prudent consumer is confused, it's powerful evidence of infringement.
• The junior user's intent in adopting the mark. If the junior user adopted the mark in bad faith, confusion is more likely.
• Quality of the junior user's products or services. In some cases, the lesser the quality of the junior user's goods, the more harm is likely from consumer confusion.
• Sophistication of the buyers. The less sophisticated the purchaser, the more likely the confusion.

While courts will typically look to the Polaroid factors, the USPTO relies primarily on variables known as the duPont factors to examine likelihood of confusion. These factors vary slightly from the Polaroid factors. We'll discuss the duPont factors later.

Breaking Down the Polaroid Factors

Every federal circuit in the U.S. uses a multi-factor analysis in determining if there is a likelihood of confusion. Although the number of factors can vary from each federal circuit, the principles are similar and all relate in some way to consumer perception.

Strength of the Mark

Trademarks exist on a distinctiveness spectrum. The more distinctive a mark is, the stronger it is. Stronger marks are afforded higher levels of legal protection.

A mark is "weak" if it's either:

• generic (like "coffee shop"), or
• descriptive and hasn't acquired sufficient secondary meaning.

A mark is "strong" if it's:

• descriptive but has acquired sufficient secondary meaning (in other words, consumers identify the mark as a source of the goods or services rather than as a description of the goods or services)
• suggestive
• arbitrary, or
• fanciful (a made-up term).

When you evaluate the strength of a mark, you look at how the mark relates to its associated goods and services. "Descriptive marks" are those that describe some ingredient, feature, quality, or aspect of the connected goods or services. "Suggestive marks" are marks that suggest a connection between the mark and the goods and services but the connection isn't immediately obvious. As the name would imply, an "arbitrary mark" is one that has no relation to its connected goods or services—like Apple for computers.

The owner of a weak mark will have difficulty proving likelihood of confusion. For example, the mark, "Maid in America" for cleaning services was determined to be descriptive. The owner was unable to demonstrate a sufficient showing of advertising or sales to prove secondary meaning. Therefore, the trademark owner didn't prevail in a claim of infringement against a similar mark.

If descriptiveness is an issue in an infringement action, the party trying to prove infringement can conduct a survey to prove secondary meaning. In addition, marks that have existed for five or more years can also acquire secondary meaning.

Similarity of the Marks

As a general rule, marks must be compared in their entireties in a likelihood of confusion analysis. Specifically, you must consider a mark's:

• appearance
• sound
• connotation, and
• commercial impression.

However, you might need to dissect the marks and compare the individual elements of each mark to assess the similarities.

In one case, the owner of the mark OAG Travel Planner sued the owner of the mark The Travel Planner. The court determined that the mark Travel Planner was descriptive and weak, but that the use of OAG in conjunction with "Travel Planner" created an arbitrary mark. Since there were similarities in sight and sound, the court determined that the marks were likely to confuse customers. Similarly, a court found similarity between Dutch Masters and Little Dutchman for cigars because of the common use of the dominant term "Dutch."

Adding a prefix or suffix, changing letters or adding clarifying information might not avoid a claim of similarity of marks. For example, the following marks were found to be similar: Magnavox and Multivox; Simoniz and Permanize; Platinum Puff and Platinum Plus; Zirco and Cozirc; and Maternally Yours and Your Maternity Shop.

In addition, the similarity of the meaning of the marks can also be taken into consideration. For example, the following marks were held to be similar: Mr. Clean and Mr. Rust and Mr. Stain; Thirty Forty Fifty and 60 40 20; and Pledge and Promise.

Similarity of the Goods or Services

The standard of infringement is whether an ordinary prudent purchaser would be likely to purchase one item, believing they were purchasing the other. For example, Chlorit when used on bleach is likely to be confused with Chlorox.

As a general rule, a trademark owner can use a similar mark as long it's on completely dissimilar goods. In other words, a company can use the same name as yours as long as they provide different goods or services. For example, the use of the mark Lexus on automobiles was determined not to confuse consumers of the Lexis legal database services.

The protection afforded to a trademark owner can extend to related goods. For example, a trademark for canned salmon can also extend to other canned fish. Use of a mark on kerosene lamps can extend to electric lamps. In a case of likelihood of confusion, courts consider whether the buying public would reasonably expect that the goods or services came from the same source (provider).

The courts also consider the similarity of the advertising and distribution channels. Many courts weigh this evidence separately to determine if consumers or distributors might be exposed to potential confusion. For example, if the plaintiff sells salami directly to consumers but the defendant only sells salami in bulk to delicatessens, that difference could be an important factor in avoiding a claim of infringement.

Degree of Care Exercised By the Consumer

The degree of care exercised by the consumer varies according to the purchase. Generally, a buyer making a very expensive purchase is more likely to be discriminating and is less likely to be easily confused by similar marks. The reason for this higher degree of care is because the consumer is making a larger investment and they likely buy expensive items less frequently. You'd probably put a little more research into buying a boat than a sticker book, for example.

Courts assume that purchasers of real estate services, insurance, and other high-ticket items are likely to be more discriminating and source-conscious. Under these circumstances, the courts require a more substantial showing of similarity to justify a claim of likelihood of confusion.

The same is true for items that are purchased by "professional buyers." A professional buyer is a person who arrives at the purchasing point already knowledgeable about the goods (e.g., a pharmacist, physician, architects, builders, etc.) A professional buyer is less likely to be confused because of their superior knowledge as to purchasing decisions.

An ordinary purchaser, particularly one that buys inexpensive items on impulse is the most likely to be confused by similar marks. This consumer, for example, may quickly scan the aisle of a supermarket and impulsively purchase a box of garbage bags without realizing that she has been confused as to the choice of brands. In this instance, a lesser degree of care has been exercised. Therefore, less similarity may be necessary to prove likelihood of confusion.

Defendant's Intent

Although the intent of the defendant isn't essential in proving infringement, it's a relevant factor. A party intending to cause confusion will generally be successful in doing so.

However, direct evidence of the defendant's intention to deceive is usually hard to come by. Typically, the plaintiff must depend on circumstantial evidence such as how the defendant's mark was chosen or whether the defendant continued use of the mark after plaintiff's warning.

Actual Confusion

Proof of actual confusion isn't essential in determining trademark infringement. However, such evidence can be compelling in an infringement case. Sometimes companies conduct surveys to determine actual confusion. These surveys are expensive and if improperly performed, they could subvert the plaintiff's case.

USPTO Examination of the DuPont Factors

While courts typically look at the Polaroid factors, in whole or in part, the USPTO has adopted the DuPont factors when analyzing a likelihood of confusion case. Like the Polaroid factors, not every DuPont factor is relevant to any given case. The USPTO sometimes considers only two or three of the factors and disregard the other factors.

The DuPont factors consist of six factors:

• The similarity or dissimilarity of the marks. This factor is essentially the same as the coordinating Polaroid factor.
• The relatedness of the goods or services described in the application or registration. This factor is again the same as the Polaroid factor except that the USPTO will only consider the good or services as they are specifically described in the trademark application or registration.
• The similarity or dissimilarity of established trade channels. For example, the USPTO will consider whether the goods or services are marketed toward manufacturers or suppliers vs. the public at large, in wholesale to hospitals or individually to patients, or to one industry over another.
• The conditions under which the sales are made and the kinds of buyers the sales are made to. The USPTO will determine how much research, time, and thought is put into a purchase. Is it an impulse buy or does it require careful comparison and consideration? The USPTO will also look at how knowledgeable the typical consumers are in a particular field.
• The number and nature of similar marks in use on similar goods. The USPTO will look to see whether other marks for similar goods have already been federally registered. If the marketplace is already filled with similar marks, then it becomes a harder case for one mark to exclude another from registration.
• Existence of a consent agreement. If the party trying to register a mark has acquired a consent agreement from the owner of a registered mark, then the letter is compelling evidence in favor of registration. A consent agreement basically says that the senior owner of the registered trademark doesn't think that there will be consumer confusion and that they're okay with the junior user registering their mark.

The USPTO has expressed that the first two factors—similarity of the marks and similarity of the goods or services—are the two most important factors in a likelihood of confusion analysis. So, the USPTO will likely give the most weight to those factors when evaluating your trademark application.

The best way to avoid a likelihood of confusion issue is to consult a trademark lawyer. They can conduct a trademark search for you where they identify any marks that could likely be confused with your proposed mark. If you've already received a likelihood of confusion refusal, an attorney can also help you assess the likelihood of overcoming the refusal and draft an argument for you. If you think someone else is infringing on your trademark rights, an experienced lawyer can send a cease-and-desist letter and defend your business against trademark infringement.