How Does Facebook Know I'm Jewish?

UPDATE: See below for Katan's answer

The ad nailed it.

"Hey Jew" it called out.

But how? How did it do it? I don't list my religion (or my politics) on my Facebook profile. I don't even have those Israeli flag Facebook apps.

Some plausible theories are that the marketer used some combination of targeting around my city (New York), alma mater (Binghamton) and entertainment interests (The Daily Show, Seinfeld, Everything Is Illuminated).

Some less plausible theories: top secret Jew-havioral targeting algorithms... perhaps that's what'll be unleashed at Facebook's F8 next week. Or it's just targeting people who look Jewish.

I tried calling and emailing Katan Adventures, which ran the ad. I'll let you know when I get to the bottom of this.

Still, it's better than Facebook calling people fat.

Update: Katan responded to me. I like the theories listed in the post and comments better, but at least we have an answer. I wrote:

Random question for you...

I just saw your Facebook ad where it says "Hey Jew" and it cracked me up.

I happen to cover online ad targeting on my blog and through the trade pub MediaPost, and I'm wondering how you targeted it, as I don't list my religion on my profile. Are you just targeting fans of Seinfeld or something?

Best,

David

Here's what Katan wrote back:

Hey David -

I assume you are from NY?  In order to reach Jews who haven't listed their religion on Facebook (which, by the way, is the vast majority) we run ads in metro areas with large Jewish populations and try to grab their attention with ridiculous lines such as "hey jew" but we obviously get a lot of wasted clicks with this strategy as well.   And some angry emails.

Seinfeld fans is a good idea though.  And maybe Zabar's fans, but I'm sure that is a small group.

Thanks for your interest and if you ever want to pass along any online marketing ideas, we'd love to hear them.