Document Type


Publication Date

Spring 2013


We report on the results of a two-part study, including three online consumer surveys and a coding study of the results when 2500 trademarks were run through three search engines. Consumer goals and expectations turn out to be quite heterogeneous: a majority of consumers use brand names to search primarily for the branded goods, but most consumers are open to purchasing competing products. We find little evidence of traditional actionable consumer confusion regarding the source of goods, but only a small minority of consumers correctly and consistently distinguished paid ads from unpaid search results, or noticed the labels that search engines use to differentiate paid ads from unpaid search results.

Although we do find some evidence of confusion, the types of confusion we document do not map neatly onto the categories recognized by U.S. trademark law. Our findings suggest that the development of the doctrine in this area has not been well served by the reliance of judges on casual empiricism in resolving these disputes. Much remains to be done to ensure that trademark doctrine is empirically well-grounded, and "fits" the online context. Part II provides some context for this dispute, including background on search engines and keyword searches. Part III outlines the extensive litigation, both foreign and domestic, over the use of trademarks as keywords, and identifies six assumptions that judges have made in resolving these cases. Part IV presents our empirical results. Part V discusses our findings, and Part VI concludes.

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