Click here to preview the new Fast Company

Want to try out the new

If you’d like to return to the previous design, click the yellow button on the lower left corner.

Marketers Use Email Cookies To Develop Personalized Ads

Web ads know who
you are—and where you go. But is that so bad?

Illustration by Dustin Wallace
Illustration by Dustin Wallace

Say you call MetLife Auto & Home for a quote. MetLife emails you to confirm. Then you go web surfing and there's MetLife in the ad banner of a news site. You use a search engine and there's MetLife's ad again. It's as if the firm is following you.

And it is—all because you opened that email.

This is the newest, potentially spooky front in direct advertising—something Responsys, a leader in its usage and the marketing firm behind such campaigns for MetLife and Dollar Thrifty, calls "retargeting." Why? "We targeted you the first time when we sent you an email. Now we know you're interested, so we're retargeting you in a new location," says Responsys CEO Dan Springer. "That's just being a smart marketer."

The system works through cookies—nothing new, though marketers are just now learning to drop a cookie through email and then follow potential clients. Responsys uses a network of ad exchanges to show up just about anywhere its clients want to reach a customer. It's mostly automated, but companies can personalize ads too— everything from "Buy MetLife!" to "MetLife in Miami!" to "Hey Jodi, your Honda needs MetLife!"

Not that Responsys will go that far: "I wouldn't recommend you risk the creepiness," Springer says.

The system is good news for websites. "Marketers' love affair with display media is back," says Forrester Research's 2011 report, which expects the once-sagging online display-ad market to jump 36% (to $27.6 billion) in five years. In part that's because retargeted ads boost the value of cheap, buried ad space—stuff that often sells in bulk but that marketers will spend more for if it's used in a targeted way.

It seems worth the cash: Of people who engage with MetLife because of display ads, about 75% now come through retargeting.

"We want to be able to put out a message that people relate to," says Rick Heffernan, MetLife Auto & Home's director of Internet sales strategy. "There's a connotation that this is all very invasive. But I would say that the opposite is very scary too—because then you have a lot of ads that don't apply to you."

Follow Jason Feifer @heyfeifer and @fastcompany on Twitter.

Which of These Books Are Real?

Add New Comment


  • Mick

    NIce article. Yeah retargeting is growing, And done well (without the creepiness) it's VERY effective. We've been busy putting together tactics and a cheat sheet to help savvy marketers take either their first steps with retargeting, or to seriously accelerate their existing online marketing campaigns. It's all over at We'd love your thoughts :)

  • Michael Galvin

    Smart marketing- about time somebody figured out how to link em programs to display advertising! /Michael