Madrid: Real Madrid released a statement late Monday saying it complies fully with FIFA's rules on transfers involving minors, after acknowledging that football's governing body is looking into previous deals.
Earlier, during Lucas Silva's presentation, club director Emilio Butragueno said he knew FIFA had asked the Spanish federation for documents relating to the transfers of minors to Madrid over the past five years.
Butragueno said "we are in agreement with FIFA in this matter," and that we will continue collaborating with them in everything that is asked of us. We are absolutely calm about how Real Madrid has proceeded."
FIFA exerts rigid control over international transfers of minors.
In the statement Madrid said FIFA has asked for information about 51 players, but said a majority of them were exempt from regulations for various reasons.
Among the exemptions cited by Madrid were that 10 were Spanish nationals, and 23 foreign players had already been registered with a Spanish club.
On Thursday, Madrid signed 16-year-old Norwegian midfielder Martin Odegaard from Norwegian club Stroemgodset.
Archrival Barcelona fell foul of FIFA's rules on registering minors in February 2013 and had a transfer ban imposed on it that means the Catalan giant cannot sign any new players until 2016.
FIFA found that Barcelona had violated those regulations when it signed 10 players under the age of 18 to its academy.
In December, Barcelona had its appeal against the ruling dismissed by the Court of Arbitration for Sport.
While Madrid does not have a youth academy that includes a boarding school for minors like Barcelona's renowned La Masia, it does operate youth teams.
Spain's federation said it had no comment.