Stock in Snap, the owner of the social media site Snapchat, plummeted this week after pop star Rihanna blasted the company over an ad she found offensive, CNN reports.

“The singer tore into the app on Thursday for allowing an offensive ad to appear on its platform,” the story reports. “Her remark sent Snap’s stock down nearly 4%, erasing nearly $800 million from its market value. Snap’s stock closed down 1% on Friday.”

The report adds: “The ad in question was for the mobile game ‘Would You Rather?,’ and it presented users with two options: ‘Slap Rihanna’ or ‘Punch Chris Brown.’ Brown pleaded guilty in 2009 to beating Rihanna during an argument while they were dating.”

In response to the ad, Rihanna put out a statement on Instagram saying: “Now SNAPCHAT I know you already know you ain’t my fav app out there! But I’m just trying to figure out what the point was with this mess! I’d love to call it ignorance but I know you ain’t that dumb. You spent money to animate something that would intentionally bring shame to DV victims and made a joke of it.”

Snap was distancing itself from the ad, saying in a statement provided to CNN: “We are investigating how that happened so that we can make sure it never happens again.”