We’ve gone from the face that launched a thousand ships to those that prompt a billion clicks. Tampering with the raw ingredients for such online popularity could cost a social-media company like Facebook ’s Instagram a great deal of money.

Influencers—social-media celebrities who can spark buying decisions—are akin to huge businesses in their own right. Companies pay some $2 billion annually to individuals who promote their brands on Instagram alone, according to Instagram tool Hopper HQ. Reality-television star and billionaire Kylie Jenner purportedly earns $1.27 million each time she shares a captioned photo with her more than 143 million followers. Kim Kardashian West earns just shy of $1 million per post on the platform, while siblings Khloe Kardashian and Kendall Jenner rake in hundreds of thousands of dollars each, according to Hopper HQ.

You can’t buy stock in a Kardashian—at least not yet—but you can own the next best thing. Celebrities have established a symbiotic relationship with Instagram, which Facebook bought in 2012 for $1 billion. Various estimates have pinned its value at as much as 100 times that purchase price today. That calculation may be more than an academic exercise if political pressure on technology giants ever causes them to be broken up.

But there is a more immediate question, too. Under pressure, Facebook has been working this year to make significant changes to its platforms to focus on privacy and safety for its users. In a recent test, Instagram has been hiding publicly viewed “likes” in several markets. Though it was touted as a way to decrease social pressure and improve users’ happiness, the test threatens to upend influencers’ business models and could boomerang to hurt Facebook itself.

Instagram says it doesn’t receive compensation directly for the sales it enables through hosting influencers’ posts. Instead, it basks in the traffic they bring. The more people engage on their platform, the greater its value to advertisers.