Q: Kim Kardashian's denying that she doctored her butt selfie, but why would she do such a thing in the first place? It's just an Instagram photo.

Unless it isn't. Here's a little secret: There are civilian selfies — duck-faced tweens hoping to get a follow from Harry Styles — and there are celebrity selfies. Civilian selfies aren't worth anything. Celebrity selfies, even ones featuring little more than a butt and a mirror, could be worth thousands of dollars. With money on the line, it shouldn't come as any surprise that stars may be prettifying themselves, just in case a big brand comes along offering a fat stack of cash. (Either that, or they're simply vain and just want to look good!)





Kardashian's suspicious photo doesn't appear to be a commercial enterprise. (There's also no clear-cut way to prove whether or not it's been touched up.) But in the past 10 months, more and more stars and big brands have been hooking up with the express purpose of pimping clothing, makeup, and other products via supposedly spontaneous Instagram posts. For pay.

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"We have over 200 influencers signed with us, and the number is growing," says Eric Dahan, co-founder and director of the Instagram-based marketing company Instabrand. Some of those folks are traditional celebrities; others are more Internet famous, such as the founder of the fashion blog We Wore What, Dahan tells me.



"This kind of influencer-based marketing is the marketing of the future," he notes. "There's nothing more powerful than getting a message from someone you are already paying attention to.



"It's easily a multibillion industry in the next few years. All fashion brands, if they are not participating in this, will in the next six months."



The deals typically work like this: A star posts an "organic"-looking selfie wearing, say, Joe's Jeans, or a dress from the label Revolve; both brands are Instabrand clients. By law, the influencer has to disclose, via a watermark or other indicator, that a post results from a tit-for-tat agreement. (That said, don't believe every supposedly spontaneous Instagram photo you see. As Greenberg Glusker entertainment litigator Glen Rothstein puts it, "The issue is, how do you really police these things?”)













[Related: Totally TMI Selfies]

Take a look at a recent post by Kim K., honored recipient of two pairs of Zanotti shoes … for her baby. Paid? Unpaid? Just a thank you for some completely unnecessary swag? Unclear.

Meanwhile, Nicole Richie recently re-grammed a photo featuring Joel Madden and their son in Nike sneakers. It's been reported that Nike is doing paid social media deals, but it's unclear if this is one of them.

Depending on the number of "likes" a post gets, the celeb can earn $500 to $5000 with a single photo. Another source told me that the numbers are closer to $7,500 per selfie. And that's for a rising entertainer that most people have never heard of.

But some Instagram deals simply result from stars getting free stuff. According to one source interviewed for this story, Kourtney Kardashian in April posted a photo of a bunch of goodies she got from the baby company Oliver and Adelaide. The brand had sent her the products for free.



"It's the most valuable type of endorsement right now," publicist and manager Lizzie Grubman tells me. "Instagram is such a visual medium."





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Leslie Gornstein is an entertainment writer and the host of the weekly Hollywood gossip podcast The Fame Fatale.