How Does the USPTO Evaluate Likelihood of Confusion Using DuPont Factors?

The USPTO evaluates trademark likelihood of confusion by reviewing all 13 DuPont criteria on a qualitative sliding scale based on real-world marketplace realities. Examining attorneys do not look at application files in a vacuum; instead, they weigh core pillars together to determine if an applied-for mark creates a conflicting overall commercial impression with a pre-existing registration.

This is exactly how the USPTO actually applies the DuPont factors:

Factor 1: Similarity of the Marks

This factor weighs the similarities of the marks in how they look, how they sound, and what they mean in the minds of consumers. 

Why it matters: Even small differences in spelling, pronunciation, or overall “feel” can be enough to create confusion when goods or services are related.

Example: Registering “Klear” for cleaning products when “Clear” is already registered in the same field is legally refused.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 1, applicants must emphasize differences in commercial impression and overall look-and-feel rather than nitpicking minor spelling variations. Provide clear side-by-side comparisons in your response. Do not waste arguments on minor spelling or visual differences.

Factor 2: Relatedness of the Goods or Services

This factor determines whether the relevant products or services are commercially connected, complementary, or associated within the minds of ordinary consumers. 

Why it matters: When goods or services are unrelated, consumers are unlikely to assume they come from the same source, even if the marks share some similarity.

Example: The mark “Delta” is used successfully by both a major airline and a plumbing fixtures company because airplanes and bathroom faucets are entirely unrelated goods.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 2, applicants must clearly distinguish your goods or services from those listed in the cited registration. Use precise descriptions and, when helpful, marketplace evidence showing how the industries differ.

Factor 3: Similarity of Established Trade Channels

This factor examines where and how the businesses market, distribute, and sell their products or services.

Why it matters: When two brands target the same customers through the same stores, websites, or distribution methods, the risk of confusion rises significantly.

Example: Two independent clothing creators using similar brand names to sell custom t-shirts on Etsy face higher risk because their trade channels are identical.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 3, applicants must highlight meaningful differences in sales channels, target customers, price points, or distribution methods when they exist.

Factor 4: Conditions of Sale and Buyer Sophistication

This factor measures the degree of care and deliberation a consumer exercises before making a purchase.

Why it matters: Sophisticated buyers who research carefully are less likely to be confused by similar marks than impulse purchasers.

Example: Corporate procurement managers buying a $50,000 enterprise software suite research vendors thoroughly, while an impulse shopper grabbing a $5 candy bar makes a quick decision with little research.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 4, applicants must emphasize high price points, long sales cycles, expert purchasers, or complex decision-making processes when they apply to your goods or services.

Factor 5: Fame of the Prior Mark

This factor considers the level of recognition and fame of the earlier mark.

Why it matters: Extremely famous marks receive significantly broader protection and can block registration even in unrelated fields.

Example: A local computer repair shop named “Nike Tech Fix” would likely be refused because the extreme fame of the Nike athletic brand overrides the difference in industries.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 5, applicants must focus on strong distinctions in the other key factors (especially 1 and 2) and consider whether a consent agreement may be necessary. Famous marks are difficult to overcome.

Factor 6: Number and Nature of Similar Marks in Use

This factor explores whether the mark (or similar terms) is already widely used by third parties in the same or related fields.

Why it matters: When many businesses already use similar terms, the prior mark is considered weaker, and consumers are better at distinguishing between them.

Example: If dozens of fitness businesses already use the word “Summit,” the USPTO is more likely to allow “Summit Elite Training” because consumers already differentiate between various “Summit” gyms.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 6, applicants must submit evidence of third-party registrations and real-world marketplace uses (the “crowded field” argument). This is often one of the most effective ways to overcome a refusal.

Factor 7: Nature and Extent of Actual Confusion

This factor considers evidence showing that real consumers have actually mistaken one business for another.

Why it matters: Documented instances of confusion provide strong proof, although the absence of actual confusion does not automatically disprove likelihood of confusion.

Example: Customer service logs showing buyers repeatedly calling a rival restaurant to place orders serves as compelling evidence of actual confusion.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 7, applicants need to focus primarily on the stronger factors (1–3) unless they have clear documentation of actual confusion.

Factor 8: Length of Time of Concurrent Use Without Confusion

This factor examines whether the marks have coexisted in the marketplace for a significant period without documented consumer confusion.

Why it matters: Long, peaceful coexistence strongly suggests that future confusion is unlikely.

Example: Two regional bakeries using variants of “Sweet Treats” operating in neighboring towns for 10 years with no mixed-up deliveries or customer complaints provide excellent supporting evidence.

Applicant Strategy: If applicable, document the length of concurrent use and the absence of any confusion incidents. This factor carries more weight when the period of coexistence is substantial.

Factor 9: Variety of Goods on Which a Mark Is Used

This factor looks at whether the prior mark is used on a narrow range of goods or as a broad “house brand” that expands across many categories.

Why it matters: Well-known house brands (such as GE or Sony) that routinely expand into new product lines receive broader protection than single-product brands.

Example: A mark used only on one narrow product line generally has more limited protection than a famous house mark used across electronics, appliances, and financial services.

Applicant Strategy: This factor is not relevant unless the cited mark is a broad, well-known house brand.

Factor 10: Market Interface Between Parties / Consent Agreements

This factor considers formal agreements between the parties, particularly consent or coexistence agreements.

Why it matters: A properly drafted consent agreement in which the owner of the prior mark gives written permission for registration can carry significant weight.

Example: An existing trademark owner signs a coexistence agreement that limits the new applicant’s goods, services, or trade channels in exchange for consent to register.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 10, applicants must present a structured coexistence agreement with meaningful limitations on use. A bare statement of consent has limited value. A rigorous and structured coexistence agreement is far more persuasive to examining attorneys.

Factor 11: Extent to Which Applicant Has a Right to Exclude Others

This factor considers the scope of the applicant’s existing trademark rights and ability to prevent others from using similar branding.

Why it matters: Highly descriptive or weak marks have narrower exclusionary rights, which can affect how the USPTO views the overall strength of the applicant’s position.

Example: A merely descriptive mark generally has limited ability to exclude others compared with a strong, arbitrary, or fanciful mark.

Applicant Strategy: This factor is only relevant when you already own prior registrations that strengthen your position.

Factor 12: Extent of Potential Confusion

This factor evaluates whether the risk of consumers being misled is substantial or merely minimal and incidental.

Why it matters: When the actual marketplace overlap between the parties is very limited, the potential for meaningful confusion decreases.

Example: One brand sells exclusively through secure government bids while the other sells only on social media and direct-to-consumer websites — the scope of potential overlap is minimal.

Applicant Strategy: To overcome a Section 2(d) refusal using DuPont Factor 1, applicants must clearly demonstrate limited real-world overlap in customers, channels, or geographic reach when it exists.

Factor 13: Any Other Probative Fact

This is the catch-all factor that allows examining attorneys to consider any other relevant evidence or marketplace realities not covered by the first 12 factors.

Why it matters: Unique trends, consumer behaviors, or industry-specific conditions can influence how consumers perceive the source of goods or services.

Example: Rapid changes in an industry (such as new technology platforms or shifting consumer habits) may affect whether confusion is likely.

Applicant Strategy: This factor is a catch-all. Use it to introduce any distinctive marketplace facts that support your position and are not addressed elsewhere.