A tune so appealing it went viral, now the South Korean manufacturers of the tune Baby Shark are having their day in court.
They are being taken legal action against by performer Johnny Just, who mentions he produced his version of the song in 2011.
However the South Korean manufacturers state they based their song on a popular campfire tune.
The case has in fact been handed over to a copyright commission in South Korea to pick.
Al Jazeera’s Rob McBride reports from Seoul.