The self-regulatory group Network Advertising Initiative on Thursday unveiled a new mechanism for consumers to opt out of receiving targeted ads based on hashed versions of their email addresses.
“If they're going to target using a hashed email address, they have to provide an opt-out for that hashed email address,” Anthony Matyjaszewski, the organization's vice president for compliance, says.
Two years ago, the organization issued new rules that allow members to link “hashed” or encrypted versions of consumers' email addresses with their online activity, on an opt-out basis. (Hashing converts the actual email addresses into an alphanumeric string of characters.)
At the time, companies were primarily using hashed emails for onboarding, or “audience matching” -- which enables marketers to match encrypted versions of email addresses in their databases with the addresses held by platforms like Facebook, and then send ads to those customers while they are online.
Since then, some companies have been promoting targeting platforms that rely on tracking logged-in users across sites based on hashed email addresses.
Those email-based targeting systems have largely sprung up in response to news that Google plans to join Mozilla and Apple in blocking ad-tech companies from setting cookies in users' browsers. For years, ad-tech companies relied on those cookies to track users across sites in order to build profiles that were used for personalized ads.
It's not clear how privacy-conscious consumers -- particularly ones who are concerned about receiving spam -- will respond to requests for their email addresses to effectuate opt-outs.
Matyjaszewski says he hopes the NAI's status as a nonprofit and privacy organization will “help consumers feel more trusting.”
Consumers also sometimes offer potentially contradictory information regarding privacy preferences -- such as by attempting to opt out of targeted ads, but then providing their email addresses to a specific marketer and opting in to receive ads from that company.
When that type of “collision” occurs, the NAI allows ad-tech companies to use consumers' email addresses to serve targeted ads, but only on behalf of the specific marketer that obtained the consumers' opt-in consent, according to Matyjaszewski.
NAI members that draw on consumers' hashed email addresses for tailored advertising are “expected to integrate” with the new mechanism, the organization stated Thursday.
Some companies belonging to the self-regulatory group -- including Oracle Advertising, Neustar, Criteo, Inmar Intelligence and Verizon Media -- have begun integrating with a beta version of the email-based opt-out system, the NAI says.