Facebook rejected ads that Signal tried to buy on Instagram, which sought to highlight the types of data it collects from its users, the encrypted messaging service said in a blog post Tuesday.
In a blog post titled The Instagram ads Facebook won't show you, Signal said it created a "multivariant targeted ad" that would "show you the personal data that Facebook collects about you and sells access to."
The proposed ads would have informed Instagram users of the kind of data Facebook collects, according to screenshots shared by Signal. For example: "You got this ad because you're a K-pop-loving chemical engineer. This ad used your location to see you're in Berlin. And you have a new baby. And you just moved. And you're really feeling those pregnancy exercises lately."
"The ad would simply display some of the information collected about the viewer which the advertising platform uses. Facebook was not into that idea," Signal wrote, sharing another screenshot that showed its Instagram ad account had been disabled.
"Being transparent about how ads use people's data is apparently enough to get banned; in Facebook's world, the only acceptable usage is to hide what you're doing from your audience," the company wrote in its post.
Facebook taps your personal information to precisely target ads to you -- a business that provided nearly all its $85.9 billion last year. But Facebook's data collection practices have come under scrutiny following a controversy involving Cambridge Analytica, a digital consultancy with ties to the Trump presidential campaign that improperly obtained data on up to 87 million Facebook users without their permission.
Facebook didn't immediately respond to a request for comment but in a statement to The Information dismissed the episode as a "stunt" on Signal's part.
"This is a stunt by Signal, who never even tried to actually run these ads -- and we didn't shut down their ad account for trying to do so," Facebook told the news outlet.