Likelihood of Confusion on the Internet

In cases involving claims of trademark infringement on the Internet, the Ninth Circuit has affirmed the use of an additional instruction indicating that three of the Sleekcraft factors:

(i) similarity of plaintiff’s and defendant’s mark;

(ii) relatedness of services; and

(iii) simultaneous use of the internet as a marketing channel, otherwise known as the “Internet Troika,” are of the “greatest importance.”

Internet Specialties West, Inc. v. Milon-Digiorgio Enters., 559 F.3d 985, 989 (9th Cir. 2009).

The rest of the Sleekcraft Factors are below.

Likelihood of Confusion tests-Circuit Courts

Every federal circuit court uses a different set of rules for testing the Likelihood of Confusion for trademarks, service marks and trade dress. These rules or tests are sometimes referred to as multifactor likelihood of consumer confusion tests or the “MFLOCC” test.

The Ninth Circuit Model Jury instructions are shown below because these instructions give not just the rule but also give a brief explanation.  

For the Ninth Circuit, the Sleekcraft Case is the test that is used. Not every factor is important to every case. As a potential trademark registrant, adopting a mark that will be unlikely to cause confusion may result in a faster and less expensive registration process and more protection in an infringement suit (if someone infringes you) or protection from infringement suits (you were careful not to infringe any prior users of confusingly similar marks).

The other circuit courts’ Likelihood of Confusion tests follow. In some cases, the tests have been modified by other cases (not shown) to give additional instructions for particular cases, such as the “Internet Troika” shown above.

Ninth Circuit Model Jury Instructions


You must consider whether the defendant’s use of the trademark is likely to cause confusion about the source of the plaintiff’s or the defendant’s goods. I will suggest some factors you should consider in deciding this. The presence or absence of any particular factor [ ] should not necessarily resolve whether there was a likelihood of confusion, because you must consider all relevant evidence in determining this. As you consider the likelihood of confusion you should examine the following:

1. Strength or Weakness of the Plaintiff’s Mark. The more the consuming public recognizes the plaintiff’s trademark as an indication of origin of the plaintiff’s goods, the more likely it is that consumers would be confused about the source of the defendant’s goods if the defendant uses a similar mark.

2. Defendant’s Use of the Mark. If the defendant and plaintiff use their trademarks on the same, related, or complementary kinds of goods there may be a greater likelihood of confusion about the source of the goods than otherwise.

3. Similarity of Plaintiff’s and Defendant’s Marks. If the overall impression created by the plaintiff’s trademark in the marketplace is similar to that created by the defendant’s trademark in [appearance] [sound] [or] [meaning], there is a greater chance [that consumers are likely to be confused by defendant’s use of a mark] [of likelihood of confusion]. [Similarities in appearance, sound or meaning weigh more heavily than differences in finding the marks are similar].

4. Actual Confusion. If use by the defendant of the plaintiff’s trademark has led to instances of actual confusion, this strongly suggests a likelihood of confusion. However actual confusion is not required for a finding of likelihood of confusion. Even if actual confusion did not occur, the defendant’s use of the trademark may still be likely to cause confusion. As you consider whether the trademark used by the defendant creates for consumers a likelihood of confusion with the plaintiff’s trademark, you should weigh any instances of actual confusion against the opportunities for such confusion. If the instances of actual confusion have been relatively frequent, you may find that there has been substantial actual confusion. If, by contrast, there is a very large volume of sales, but only a few isolated instances of actual confusion you may find that there has not been substantial actual confusion.

5. Defendant’s Intent. Knowing use by defendant of the plaintiff’s trademark to identify similar goods may strongly show an intent to derive benefit from the reputation of the plaintiff’s mark, suggesting an intent to cause a likelihood of confusion. On the other hand, even in the absence of proof that the defendant acted knowingly, the use of plaintiff’s trademark to identify similar goods may indicate a likelihood of confusion.

6. Marketing/Advertising Channels. If the plaintiff’s and defendant’s [goods] [services] are likely to be sold in the same or similar stores or outlets, or advertised in similar media, this may increase the likelihood of confusion.

7. Purchaser’s Degree of Care. The more sophisticated the potential buyers of the goods or the more costly the goods, the more careful and discriminating the reasonably prudent purchaser exercising ordinary caution may be. They may be less likely to be confused by similarities in the plaintiff’s and defendant’s trademarks.

8. Product Line Expansion. When the parties’ products differ, you may consider how likely the plaintiff is to begin selling the products for which the defendant is using the plaintiff’s trademark. If there is a strong possibility of expanding into the other party’s market, there is a greater likelihood of confusion.

[9. Other Factors. Any other factors that bear on likelihood of confusion.]

Federal Circuit-Likelihood of Confusion Test-(DuPont Factors)

(as reported in Champagne Louis Roederer, S.A. v. Delicato Vineyards, 148 F.3d 1373 (C.A.Fed., 1998)

The Court of Customs and Patent Appeals enunciated relevant factors for guidance in testing for the likelihood of confusion [the DuPont factors from E.I. DuPont DeNemours & Co., 476 F.2d 1357, 1361, 177 U.S.P.Q. 563, 567 (CCPA 1973)]. They are:

(1) The similarity or dissimilarity of the marks in their entireties as to appearance, sound, connotation and commercial impression.

(2) The similarity or dissimilarity and nature of the goods or services as described in an application or registration or in connection with which a prior mark is in use.

(3) The similarity or dissimilarity of established, likely-to-continue trade channels.

(4) The conditions under which and buyers to whom sales are made, i.e. "impulse" vs. careful, sophisticated purchasing.

(5) The fame of the prior mark (sales, advertising, length of use).

(6) The number and nature of similar marks in use on similar goods.

(7) The nature and extent of any actual confusion.

(8) The length of time during and conditions under which there has been concurrent use without evidence of actual confusion.         

(9) The variety of goods on which a mark is or is not used (house mark, "family" mark, product mark).

(10) The market interface between applicant and the owner of a prior mark:

(a) a mere "consent" to register or use.

(b) agreement provisions designed to preclude confusion, i.e. limitations on continued use of the marks by each party.

(c) assignment of mark, application, registration and good will of the related business.

(d) laches and estoppel attributable to owner of prior mark and indicative of lack of confusion.

(11) The extent to which applicant has a right to exclude others from use of its mark on its goods.

(12) The extent of potential confusion, i.e., whether de minimis or substantial.

(13) Any other established fact probative of the effect of use.

        DuPont, 476 F.2d at 1361, 177 USPQ at 567.

First Circuit-Likelihood of Confusion Test

(as reported in Borinquen Biscuit Corp. v. M.V. Trading Corp., 443 F.3d 112 (1st Cir., 2006))

This court has enumerated eight factors to guide the inquiry into likelihood of confusion [also known as the Pignon Factors]:

(1) the similarity of the marks;

(2) the similarity of the goods;

(3) the relationship between the parties' channels of trade;

(4) the relationship between the parties' advertising;

(5) the classes of prospective purchasers;

(6) evidence of actual confusion;

(7) the defendant's intent in adopting its mark; and

(8) the strength of the plaintiff's mark.

Astra Pharm. Prods., Inc. v. Beckman Instruments, Inc., 718 F.2d 1201, 1205 (1st Cir.1983); accord Pignons S.A. de Mecanique de Precision v. Polaroid Corp., 657 F.2d 482, 487 (1st Cir.1981). A proper analysis takes cognizance of all eight factors but assigns no single factor dispositive weight.

Second Circuit-Likelihood of Confusion Test

(as reported in Fed. Express v. Federal Espresso, 201 F.3d 168 (2nd Cir., 1999))

The eight factors set forth in Polaroid Corp. v. Polarad Electronics Corp., 287 F.2d 492, 495 (2d Cir.) ("Polaroid"), cert. denied, 368 U.S. 820 (1961), in order to determine whether there was a likelihood of consumer confusion. Those factors are:

(1) the strength of the plaintiff's mark;

(2) the similarity of plaintiff's and defendant's marks;

(3) the competitive proximity of the products;

(4) the likelihood that plaintiff will "bridge the gap" and offer a product like defendant's;

(5) actual confusion between products;

(6) good faith on the defendant's part;

(7) the quality of defendant's product; and

(8) the sophistication of buyers.  

Third Circuit-Likelihood of Confusion Test-The LAPP Factors

(Factors from Interpace Corp. v. Lapp, Inc., 721 F.2d 460, 463 (3d Cir.1983) as reported in Century 21 Real Estate Corp. v. Lendingtree, Inc., 425 F.3d 211 (Fed. 3rd Cir., 2005))


Multi-factor test that assesses the following:

(1) degree of similarity between the owner's mark and the alleged infringing mark;

(2) strength of the owner's mark;

(3) price of the goods and other factors indicative of the care and attention expected of consumers when making a purchase;

(4) length of time the defendant has used the mark without evidence of actual confusion;

(5) intent of the defendant in adopting the mark;

(6) evidence of actual confusion;

(7) whether the goods, though not competing, are marketed through the same channels of trade and advertised through the same media;

(8) the extent to which the targets of the parties' sales efforts are the same;

(9) the relationship of the goods in the minds of consumers because of the similarity of function; and

(10) other facts suggesting that the consuming public might expect the prior owner to manufacture a product in the defendant's market or that he is likely to expand into that market.

Fourth Circuit-Likelihood of Confusion Test

(as reported in Petro Stopping Centers, L.P. v. James River Petroleum, Inc., 130 F.3d 88 (C.A.4 (Va.), 1997)

In determining whether a plaintiff has demonstrated likelihood of confusion, courts of this circuit are guided by the factors announced in Pizzeria Uno Corp. v. Temple, 747 F.2d 1522, 1527 (4th Cir.1984). A court should consider

(1) the strength or distinctiveness of the plaintiff's mark,

(2) the similarity of the two parties' marks,

(3) the similarity of the goods and services the marks identify,

(4) the similarity of the facilities the two parties use in their businesses,

(5) the similarity of advertising used by the two parties,

(6) the defendant's intent, and

(7) actual confusion.

These factors are not of equal importance or equal relevance in every case.

Fifth Circuit-Likelihood of Confusion Test

(as reported in The Southern Company v. Dauben Inc., No. 08-10248 (5th. Cir., 2009))

The likelihood of confusion standard in trademark infringement claims involves consideration of eight nonexhaustive factors:

(1) the type of mark allegedly infringed,

(2) the similarity between the two marks,

(3) the similarity of the products or services,

(4) the identity of the retail outlets and purchasers,

(5) the identity of the advertising media used,

(6) the defendant's intent, and

(7) any evidence of actual confusion.

Sixth Circuit-Likelihood of Confusion Test

(as  reported in Wynn Oil Co. v. Thomas, 839 F.2d 1183 (C.A.6 (Tenn.), 1988))

The factors that courts should examine to determine whether the alleged infringement of a trade or service mark causes a "likelihood of confusion" among consumers. These factors include the

(1) strength of plaintiff's mark;

(2) relatedness of the goods;

(3) similarity of the marks;

(4) evidence of actual confusion;

(5) marketing channels used;

(6) likely degree of purchaser care;

(7) defendant's intent in selecting the mark;

(8) likelihood of expansion of the product lines.

These factors are simply a guide to help determine whether confusion would be likely to result from simultaneous use of the two contested marks. They imply no mathematical precision, and a plaintiff need not show that all, or even most, of the factors listed are present in any particular case to be successful.  

Seventh Circuit-Likelihood of Confusion Test

(as reported in Barbecue Max, Incorp. v. 551 Ogden, Incorp., 235 F.3d 1041 (7th Cir., 2000))

Seven factors comprise the likelihood of confusion test:

(1) similarity between the marks in appearance and suggestion;

(2) similarity of the products;

(3) area and manner of concurrent use;

(4) degree of care likely to be exercised by consumers;

(5) strength of complainant's mark;

(6) actual confusion; and,

(7) intent of defendant to 'palm off his product as that of another.’

Eighth Circuit-Likelihood of Confusion Test

(as reported in Anheuser-Busch, Inc. v. Balducci Publications, 28 F.3d 769 (C.A.8 (Mo.), 1994)

This court enumerated several factors pertinent to the finding of likelihood of confusion in SquirtCo v. Seven-Up Co., 628 F.2d 1086 (C.A.8 (Mo.), 1980):

(1) the strength of the trademark;

(2) the similarity between the plaintiff's and defendant's marks;

(3) the competitive proximity of the parties' products;

(4) the alleged infringer's intent to confuse the public;

(5) evidence of any actual confusion; and

(6) the degree of care reasonably expected of the plaintiff's potential customers.

These factors are not a distinct test, but represent the sort of considerations which a court should consider in determining whether likelihood of confusion exists.

Ninth Circuit-Likelihood of Confusion Test

(as reported in Dr. Seuss Enterprises, L.P. v. Penguin Books USA, Inc., 109 F.3d 1394 (C.A.9 (Cal.), 1997)

The eight-factor Sleekcraft test is used in the Ninth Circuit to analyze the likelihood of confusion question in all trademark infringement cases, both competitive and non-competitive. AMF Inc. v. Sleekcraft Boats, 599 F.2d 341 (9th Cir.1979). The eight factors are as follows:

(1) strength of the mark;

(2) proximity of the goods;

(3) similarity of the marks;

(4) evidence of actual confusion;

(5) marketing channels used;

(6) type of goods and the degree of care likely to be exercised by the purchaser;

(7) defendant's intent in selecting the mark; (8) likelihood of expansion of the product lines.         

These factors are to be considered in reaching a decision on the issue of likelihood of confusion. However, "[n]o mechanistic formula or list can set forth in advance" the variety of elements that comprise the market context from which likelihood of confusion must be determined. Restatement (Third) of Unfair Competition § 21, comment a (1995). The Sleekcraft court noted that this "list is not exhaustive" and "[o]ther variables may come into play depending on the particular facts presented." Sleekcraft, 599 F.2d at 348 n. 11.

Tenth Circuit-Likelihood of Confusion Test

(As reported in Utah Lighthouse Min. v. Foundation for Apologetic, 527 F.3d 1045 (10th Cir., 2008)

 Likelihood of confusion is typically evaluated according to a six-factor test in which the court considers:       

(1) the degree of similarity between the marks;

(2) the intent of the alleged infringer in using the mark;

(3) evidence of actual confusion;

(4) similarity of products and manner of marketing;

(5) the degree of care likely to be exercised by purchasers; and

(6) the strength or weakness of the marks.

Sally Beauty Co., Inc. v. Beautyco, Inc., 304 F.3d 964 (10th Cir.2002). No one factor is dispositive.

Eleventh Circuit-Likelihood of Confusion Test

(from in Tally-Ho, Inc. v. Coast Community College District, 889 F.2d 1018 (11th Cir.1989)

as reported in Carnival Brand Seafood Co. v. Carnival Brands, 187 F.3d 1307 (11th Cir., 1999))

The seven factors that this Circuit uses for determining the likelihood of confusion are

(1) the type of mark;

(2) the similarity of the two marks;

(3) the similarity of the goods;

(4) the identity of customers and similarity of retail outlets, sometimes called the similarity of trade channels;

(5) the similarity of advertising;

(6) the intent, i.e., good or bad faith, of the alleged infringer; and

(7) evidence of actual confusion, if any.  

Likelihood of Confusion refusals and other problems can be reduced or eliminated by choosing trademarks and trade names based on their inherent strength and a right-to-use strategy.

We suggest a Not Just Patents Five-Step Verification as part of a Plan for A Successful Trademark:

To Verify a potential trademark is strong, available to use, and ready to register, the process should be more than a direct hit federal search. To maximize the commercial strength and minimize the weaknesses of a trademark, a potential trademark user should:

1) Verify Inherent Strength,

2) Verify Right to Use,

3) Verify Right to Register,

 4) Verify the potential mark (as currently used) Functions As A Mark, and

5) Verify that the Goods and Services ID is both the correct and the maximum claim that are user can make and verify that the Goods and Services ID meets USPTO requirements before filing.

 See Why Should I Have A Trademark Attorney Answer My Office Action if you have already applied and been refused.

© Not Just Patents LLC, PO Box 18716, Minneapolis, MN 55418, (651) 500-7590, This web site is for informational purposes only and is provided without warranties, express or implied, regarding the information's accuracy, timeliness, or completeness and does not constitute legal advice. No attorney/client relationship exists without a written contract between Not Just Patents LLC and its client. Past performance is no guarantee of future results. Privacy Policy Contact Us