Angered over Gabriel Barbosa's sale to Inter Milan by Santos, Barcelona are now considering taking action against the Brazilian club.
The striker joined Inter Milan despite a transfer agreement signed by Barcelona and Santos in 2013 for their right to have first refusal for the player.

According to Marca, Brazilian website, UOL Esporte published a letter dated August 29 , 2016 (two days before the 2016/17 transfer window closed) signed by Santos informing Barcelona of its intent to sell Barbosa for 29.5 million Euros. Barcelona feel the time wasn't enough to allow the club negotiate and come up with a better offer for the striker.

Club president, Josep Maria Bartomeu announced in a radio interview yesterday night (September 5, 2016) that they are studying whether to file a report to FIFA or take action through the courts against Santos.

Known for his prolific goal scoring ability, Gabriel Barbosa was nicknamed Gabigol. Barbosa has been dubbed the "next Neymar" by the media.

Source: http://fulltimescores.net/2016/09/06/gabriel-barbosa-barcelona-plan-action-santos-players-transfer-inter/