v. Facebook Inc.


A judge denied plaintiff’s motion for class certification, citing Professor Hanssens’s expert report.

The plaintiff, an online advertising company, alleged that Facebook misrepresented its targeted advertising system’s capabilities. Defense counsel retained Cornerstone Research to support Dominique Hanssens of the University of California, Los Angeles.

Professor Hanssens conducted a survey of Facebook advertisers to examine the sources of information they rely on and the factors that influence their decision to advertise on Facebook.

In denying class certification, the judge directly quoted Professor Hanssens’s survey as evidence of lack of exposure and materiality on a classwide basis. The judge found that the survey results “show significant variation in the sources of information that an advertiser relies on when determining whether to use Facebook for an advertising campaign. That variance, in turn, raises individualized questions about the materiality of the interface (or its particular misstatements) to any given advertiser’s purchase decision.”

For more information, contact Alex Yavorsky.

Case Expert

Dominique M. Hanssens

Distinguished Research Professor of Marketing,
UCLA Anderson School of Management,
University of California, Los Angeles;
Senior Advisor, Cornerstone Research