OAKLAND, Calif. (CN) - Attorneys asked a federal judge on Wednesday to certify a class of Facebook users who claim the social media giant illegally mines private messages for advertising purposes.
The case, which will have major implications for privacy in Internet communications, is the first in which a party has claimed that Facebook users have property rights related to their Facebook messages.
Lead plaintiff Matthew Campbell sued Facebook in 2013 for misrepresenting the privacy of their private messages, claiming the site scanned messages from one user to another in search of URLs to third-party sites.
Campbell claims that Facebook then used that URL information to drive up the number of Facebook "likes" on third-party pages.
At Wednesday's hearing before U.S. District Judge Phyllis Hamilton, class attorney Michael Sobol said that "extensive and rather contentious and hard-fought discovery" revealed that Facebook's source code reveals "a continued systematic harvesting of private message content."
"Every time a private message is sent with a URL attachment, Facebook intercepts it, analyzes it and creates a user-specific data structure out of the content of the private message," Sobol said.
Facebook then "uses that data structure to inform itself and to inform third parties how to improve marketing," and "they also use it to boost their standing among their competitors," Sobol said.
"In a company where they have become the predominant social platform in the U.S. if not the world - where they intend to be the primary way that people interact online - how people communicate and how people share information on the Internet is incredibly important," Sobol said.
According to Sobol, investigation of Facebook's source code revealed that "confidential communications about Internet content" are known to Facebook as "share events," which are the items that Facebook intercepts, records and stores.
Facebook refers to the source code mechanism for these mining practices as an "EntShare," and "the overall pattern of the conduct here really speaks to how this case can be certified," Sobol said.
"They have all this stuff sucked up in a vast database," Sobol said. "There needs to be a limitation here on what they're exploiting under promises of privacy."
He added, "The Internet is a powerful tool for social change, but if you're going to harness that power you need to do it in a responsible and mature way.
"Frankly, this case is about no less than the future of privacy on the Internet."
Hamilton expressed a few concerns as to the proposed class definition, particularly as to the numerosity requirement for class certification.
She pointed out that there are "a lot of general numbers about Facebook users," but she asked Sobol if the discovery process had produced a concrete number of "share objects."
"I'd like to know if there's anything concrete other than just 'everybody uses Facebook'," Hamilton said.
Sobol replied, "I think the numbers are there."
Hamilton also asked whether "actual harm" would be "part of the metrics when considering statutory damages."
"How would statutory damages be assessed for a class that has engaged in multiple transmissions that were intercepted?" she asked.
Sobol answered, "We're operating under a statute, and I think it would be left to your honor's discretion in the briefing as to what would be an appropriate measure in this instance."
Christopher Chorba, who argued for Facebook, contended that "this case is ill-suited for class treatment because there are a number of individualized issues necessary to resolve plaintiffs' claims."
Sobol is with Lieff Cabraser in San Francisco.
Chorba is with Gibson Dunn in Los Angeles.
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