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Consumer Confusion short video (YouTube)

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Trademarks: Demonstrating Actual Consumer Confusion

Unlike the law of copyrights and patents, which protects the rights of inventors and creators, trademark law seeks to protect consumers.  When a consumer purchases a product and enjoys its qualities, a trademark aids that consumer in finding its manufacturer’s products again.  Thus, while a manufacturer holds a trademark, the trademark benefits consumers of the manufacturer’s product rather than the manufacturer itself.

However, enforcement of trademark law is still left largely in the hands of companies filing private actions alleging trademark infringement against other manufacturers.  The heart of this accusation of infringement is that consumers have suffered at the hands of the infringer because the infringing mark has interfered with their ability to purchase goods from a familiar manufacturer.  Thus, to succeed in a claim of infringement, a plaintiff must show “likelihood of consumer confusion.”

Notice that this standard does not require a plaintiff to show that consumers have actually been confused by the infringing mark, only that it is likely that they will be in the future.  However, if consumers have already been confused, it does not take much to show that they are likely to be confused again.  Thus, a successful showing of actual consumer confusion gets a plaintiff much of the way to success in an infringement case.  Surveys conducted using social science techniques are one commonly employed approach in getting there.


Case Study: Trademarks: Demonstrating Actual Consumer Confusion

Each of the federal Circuit Courts has developed its own multifactor test to judge the likelihood of consumer confusion.  For example, in the Second Circuit, a court considers the Polaroid Factors: “(1) the strength of the plaintiff's mark; (2) the degree of similarity between the two marks; (3) the proximity of the products; (4) the likelihood that the owner will bridge the gap; (5) evidence of actual confusion; (6) defendant's good faith in adopting the mark; (7) the quality of defendant's product; and (8) the sophistication of the consumers. will likely cause confusion with plaintiff's mark.”  Polaroid Corp. v. Polarad Elecs. Corp., 287 F.2d 492, 495 (2d Cir.1961) (internal citations omitted).        

“Courts have often emphasized the strong influence of actual confusion evidence on their likelihood of confusion determinations, often calling this factor the most important of all. The Fourth Circuit calls evidence of actual confusion "often dispositive," the Ninth Circuit has concluded that it is "persuasive proof that future confusion is likely" and the Seventh and Fifth Circuits have opined that "very little proof of actual confusion would be necessary to prove likelihood of confusion." If there are documented instances of actual confusion where the marks have been simultaneously used in the marketplace for only a short time, courts view such evidence as strongly supporting likelihood of confusion.” Jerome Gilson & Anne Gilson Lalonde, 5-5 Gilson on Trademarks § 5.04 (2006) (internal citations omitted).

B.  However, social science evidence is far from the only method of proof available for the plaintiff seeking to show actual consumer confusion.  Testimony by witnesses who were confused or documentary evidence also suffice.  Consider the strong non-social science evidence presented in one case:


“Plaintiff has provided a copy of an e-mail written by [the Defendant] to an investigator working for Plaintiff but posing as an individual interested in purchasing goods from Defendants. In the e-mail, dated March 11, 2004, [the Defendant] states: "I'm so sorry, I had almost deleted [your] e-mail as we get so very many e-mails everyday from the 'other' companies and I just naturally thought this was one of the hundreds we get every week."  Finally, Plaintiff's vice president of marketing states in her declaration that two publishers, Whole Foods Magazine and Organic Style Magazine, both of whom have business relationships with Plaintiff, mistakenly set up links from their websites to After Plaintiff contacted the magazines, they reset their links to Plaintiff's website. This evidence is sufficient to establish that actual confusion is occurring.” Garden of Life, Inc. v. Barry Letzer, 318 F. Supp. 2d 946, 966 (C.D.Ca. 2004) (internal citations omitted).

C.  One common method of showing evidence of actual confusion is to present social science survey evidence of actual consumer confusion.  But what characteristics would an effective survey have?  In 1960, a consultative group of federal judges provided guidelines:

“These criteria, which have been widely adopted by the courts in trademark cases, may be summarized as follows: (1) the "universe," or total pool from which survey respondents are selected, must be found to be the appropriate target group for the purposes of the particular survey in question; (2) the representative sample drawn from the universe must be statistically valid and appropriate under the circumstances; (3) the questions to be asked of interviewees must be framed in a clear, precise, and nonleading manner; (4) sound interview procedures must be followed by competent interviewers who have no knowledge of the litigation or the purpose for which the survey is conducted; (5) the data gathered must be accurately reported; (6) the data must be analyzed in accordance with accepted statistical principles; and (7) the objectivity of the entire process must be assured.”  98 A.L.R. Fed. 20, §2[A].

D. However, social scientists have addressed consumer confusion in contexts outside of trademark law, recognizing that consumer confusion may be caused by overchoice of products, ambiguous or misleading marketing information as well as similarities between products.  In fact, one study revealed that 9-17% of British consumers had mistakenly purchased the wrong product in the last six months.  These numbers may underestimate the rates of consumer confusion, since some instances are likely unconscious and never noticed.  Here is a broad overview of the social science approach to consumer confusion:

“Research in psychology and marketing however, suggests that the processing capacity of human memory is limited. In his seminal study, Miller argues that the processing capacity of short-term memory is limited to the magical number seven (plus or minus two) chunks of information. If more than these seven chunks of information are provided, the information processing level begins to decrease. Hence, if information becomes excessive, it negatively influences decision-making.

Also, the notion of the modern society "the more choices, the better" is increasingly questioned in psychological studies. An average small American supermarket carries 285 varieties of cookies, 85 flavors and brands of juices, and 95 varieties of chips. Customers there face 230 soup offerings, 120 different pasta sauces, 275 varieties of cereal, and 175 types of tea bags. Overall, supermarkets carry more than 30,000 items, and 20,000 new products are introduced each year. Schwartz concludes that some choice is undoubtedly better than none, but more choice is not always better than less. When consumers are exposed to excessive choice and excessive product related information, they can get confused and react with feeling of stress, frustration and sub-optimal decision making.

Turnbull, Leek and Ying define customer confusion as "consumer failure to develop a correct interpretation of various facets of a product/service, during the information processing procedure. As a result, this creates a misunderstanding or misinterpretation of the market.” 

Kurt Matzler, Martin Waiguny & Johann Füller, Spoiled for Choice: Consumer Confusion In Internet-based Mass Customization, 7 Innovative Marketing 3 (2007).

E. Integrating the social science approach with the legal one poses difficulties: two social scientists criticized the legal approach to consumer confusion:

“The law struggles to deal with disputes of passing-off and trademark infringement litigation because: both can be evidentially intensive, requiring costly market research; there can be long delays before an action goes to trail; the courts use a variety of techniques to assess the existence and extent of confusion; and there is little c onsensus on what legally constitutes confusion.  Some of these difficulties result from a lack of legal appreciation of confusion as a complex psychological construct, but even in the consumer research field, confusion measurement is fraught with conceptual difficulties and inconsistencies.  Given the potential costs of bringing or defending a legal action and the severity of possible punishments, there are compelling practical reasons for formulating a standardized confusion measure that is legally and scientifically acceptable.  The lack of a universal definition of confusion and standard ways of measuring it means that the parties have an incentive to gather as much evidence as possible, using a variety of measurement instruments, to support/refute a claim of confusion.  This can mean a lot of time and money being spent on market research.  In the meantime, the principle of “status quo” tends to delay positive judicial intervention prior to a trial, which means that injunction are not normally issued.”  Vincent-Wayne Mitchell & Ide Kearney, A Critique of Legal Measures of Brand Confusion, 357 J. Product & Brand Mngt. 8 (2002).

Legal Documents:

  1. The Starbucks Case.
  2. Polaroid
  3. Garden of Eden
  4. ALR

Social Science Articles

  1. Mitchell & Kearney, Critique of Legal Measures of Brand Confusion
  2. Matzler et al., Spoiled for Choice

Additional Information:

  1. PDF of Shari Diamond's "Reference Guide on Survey Research."
  2. Reference to Ron Gilson on Trademarks §5.04
  3. A video from the youtube channel CrashCourse that discusses the basics of trademark law and consumer confusion.