• by Wendy Davis , Staff Writer @wendyndavis, August 14, 2014

A judge has refused to dismiss a lawsuit accusing Yahoo of violating California privacy law by scanning email messages in order to surround them with ads.

U.S. District Court Judge Lucy Koh in San Jose, Calif., who issued the decision, previously ruled in a similar matter that Google might have violated the privacy rights of Gmail users. In fact, that ruling likely prompted the case against Yahoo, which was brought last October, several weeks after Koh issued the anti-Google decision.

But while the lawsuits resemble each other in many respects, they're not identical. One key difference is that the case against Yahoo was only brought on behalf of people who didn't themselves have Yahoo accounts -- and, therefore, never consented to Yahoo's terms of service.

Yahoo discloses in its terms that it scans emails in order to serve targeted ads. Koh agreed with Yahoo that those terms clearly informed users about the company's practice, and that account holders consent to the ad-related scans by accepting the terms.

But California's privacy law requires that all parties -- senders as well as recipients -- consent to the interception of electronic communications. The non-Yahoo account holders successfully argued that they should be able to proceed with their allegations, given that they never consented to Yahoo's terms of service. 

Even though the email users won this round in court, that doesn't mean that they'll ultimately get all that far. Consider, while Koh handed Google a preliminary defeat in the Gmail-privacy lawsuit, she later refused to certify it as a class-action.

Koh ruled in that case that class-action status wasn't appropriate because the key question -- whether users consented to Google's scans -- required “an intensely individualized” evaluation of the facts.

She added that people who used Gmail after coming across media accounts about the company's practices might have implicitly consented to the scans. That decision appears to have prompted a settlement, which was finalized last month.