And now everyone's suing each other.
Neymar is suing Barca over a 26m euros (£23.97m) unpaid loyalty bonus included in the contract he signed last November.
It comes after Barcelona said they were suing Neymar for 8.5m euros (£7.83m), as they want him to return the bonus paid when he signed the five-year extension.
Fifa said it had received a claim from the Brazilian against Barcelona.
On Tuesday, Neymar announced he will contest the Catalan club's lawsuit.