A naked photograph of a 14-year-old Northern Ireland girl was repeatedly posted on a Facebook "shame" page, the High Court heard on Thursday.
Lawyers for the child allege the image was obtained through blackmail and published online as a form of revenge.
She is suing the social media giant and the man suspected of posting her photograph in what is believed to be the first case of its kind in the world.
Facebook is attempting to have the claim against it dismissed, arguing that it always took the picture down once notified.
The girl, who cannot be identified, is seeking damages for misuse of private information, negligence and breach of the Data Protection Act.
Her photograph was said to have been posted on a so-called shame page several times between November 2014 and January 2016.
Barristers Edward Fitzgerald QC and Peter Girvan, representing the teenager, claim it was done in revenge and likened it to a method of child abuse. They contended that Facebook had the power to block any republication by using a DNA process to identify the image. Mr Fitzgerald told the court that it should have been a "red-line" issue for the company.
“A naked 14-year-old picture was being put on a shame page,” he said. “If they had blocked it all this subsequent publication of her naked image would not have taken place.”
Brett Lockhart QC, for Facebook, claimed the case should be struck out before it reaches trial. He relied on a European directive, arguing that it provides protection from having to monitor a vast amount of online material for what is posted on one page.
However, Mr Lockhart also stressed that the social network always respond to any reported breaches brought to its attention. Following submissions judgment was reserved on the application to have proceedings halted.