A judge in Madrid, acting on a request from the state prosecutor, ordered Neymar, his parents, former Barca president Sandro Rosell, incumbent Josep Maria Bartomeu and two former Santos officials to present themselves on Feb. 1 and 2.
Javier Faus, a former Barca vice president, was called to appear as a witness.
"The judge ... believes that the prosecutor's requests are 'relevant, necessary and balanced' for them to require an examination of the facts," the court said in a statement on Wednesday.
Neither Barcelona, Neymar or any of the other defendants could immediately be reached for comment.
The club has said it acted "fully within the law" and rejected the accusations contained in the DIS suit.