Facebook will have to face a class action lawsuit alleging it violated users’ privacy when it scanned the content of messages for advertising purposes, U.S. District Judge Phyllis Hamilton in Oakland ruled on Tuesday.

Judge Hamilton denied Facebook’s bid to dismiss the lawsuit, which was filed by Facebook users Matthew Campbell and Michael Hurley in 2013. The suit alleges that until October 2012, when the social network says it stopped the practice, it scanned the content of private messages sent between users for links to websites, which were then used for delivering targeted advertising. The complaint alleges that this violated the federal and state privacy laws by “reading its users’ personal [and] private Facebook messages without their consent.”

Facebook had argued that the practice was covered by an exception under the federal Electronics Communications Privacy Act, and that it disclosed to users that it “may use the information we received about you” for “data analysis.” But Judge Hamilton said the company had “not offered a sufficient explanation of how the challenged practice falls within the ordinary court of business,” and that the disclosure was not specific enough to establish that users expressly consented to the scanning of the content of their messages.

“Facebook’s unwillingness to offer any details regarding its targeted advertising practice prevents the court from being able to determine whether the specific practice challenged in this case should be considered ‘ordinary,’” Judge Hamilton said.


A Facebook spokesperson declined to comment on the case.

Campbell, Hurley and an additional plaintiff, David Shadpour, seek class-action status on behalf of U.S. users who sent or received private messages that included links to websites.

Twitter: @traceylien