Collecting a broad range of personal data—from device identifiers and IP addresses to sensitive information like health data—the company builds out user profiles and shares this information with entities looking to advertise through real-time bidding, meaning that consumers’ personal data is exposed not just to winning ad bidders but to a range of third parties, plaintiffs allege. 

The lawsuit also argues that The Trade Desk’s technology works as both a demand-side provider (DSP) and a data management platform (DMP), or data broker, which enables it to artificially inflate bid values with the consumer data it has collected. 

The Trade Desk, the lawsuit says, “has wrongfully and unlawfully trafficked in the named Plaintiffs’ and Class Members’ personal information and other personal data without their consent for substantial profits.” 

The Trade Desk is not only practicing what the Federal Trade Commission categorizes as high-risk behavior around real-time bidding, but is also in violation of both federal and California state privacy laws, according to the complaint. 

Proving injury may be challenging in both cases, especially in light of recent court rulings that effectively heighten the requirements for showing material harm for plaintiffs in class actions involving alleged breaches of the California Invasion of Privacy Act.

Nonetheless, the cases appear strong enough to warrant serious consideration, according to Arielle Garcia, COO of adtech watchdog Check My Ads. 

“I don’t think it’s ambulance-chasing,” she said. “It seems more likely to be a strategic litigation pursuit … [an approach that] is going to be very attractive to privacy advocates right now. I’d anticipate continued pushes at the state level, both for strong privacy legislation—as we’re seeing in Vermont and Massachusetts—and via private litigation like this. So, I wouldn’t sleep on this.”

The Trade Desk did not respond to a request for comment. 

Outside of the new legal challenges, The Trade Desk has found itself under pressure in recent weeks following subpar Q4 revenues and widespread discontent around its Kokai platform update.