The case has been brought to court by club member Jordi Cases.
The Brazil forward signed for the Spanish champions in the close season for 57.1 million euros, of which 17.1 million euros went to his former club Santos, it was said in court.
Cases is looking for clarification over what happened to the remaining 40 million euros, which Barcelona say was paid to a company, named in media reports as Neymar & Neymar.
Liga
Rosell denies 'reckless' €40m embezzlement claim
10/12/2013 AT 09:35
"It is not known what has really taken place with the 40 million euros supposedly paid to the player or his representatives," Cases said in a statement read out at the hearing on Wednesday.
The judge Pablo Ruz has given Barcelona five days to provide Neymar's contracts.
He has also asked for the club's financial records from the previous three years to cover the period during which negotiations for the 21-year-old's signing took place.
"It is a charge without basis. I am relaxed," Rosell told reporters on Monday.
Barcelona spokesman Toni Freixa said the club had nothing to hide.
"We have acted with complete transparency and we have nothing to be concerned about," he told a news conference on Monday.
"We have explained the details of the transfer... 40 million euros went to a company. If any judicial body asks for the information then there will be no problem."
Liga
Neymar presentation draws 56,500 fans
04/06/2013 AT 11:05
Liga
Atletico Madrid to buy Porto's Colombia striker Jackson Martinez - agent
23/06/2015 AT 21:29