Barcelona will not be allowed to sign any players in 2015 after their appeal against a transfer ban was dismissed by the Court of Arbitration for Sport.
The Spanish club was handed a 14-month ban in April after being found guilty of breaching Fifa's rules on the transfer of players aged under 18.
Barcelona has expressed its "utter nonconformity with the resolution".
The players concerned in the infringement of Fifa rules were registered and participated in competitions with Barcelona between 2009 and 2013.
Cas said: "The panel found in particular that FC Barcelona had breached the rules regarding the protection of minors and the registration of minors attending football academies.
"Accordingly, the Fifa decision is confirmed in full and the sanction remains in force.
"In view of the need to issue a decision before the opening of the next transfer window, the panel has issued its decision without the grounds. The full arbitral award, with the reasons for the panel's decision, will be issued as soon as possible."
A Barcelona statement added: "The errors that the club might have committed, and which have been recognised and argued before the corresponding authorities, are, in all cases, of an administrative nature and to a large extent have been caused by the existing conflict between the Fifa regulations and Spanish legislation, along with the club's conviction that it was acting correctly.
"Therefore, FC Barcelona considers the sanction to be completely disproportionate as it supposes an excessive punishment for the club, when considering its trajectory and the circumstances of this specific case."
Barca went on a summer spending spree this year while the suspension went on hold during the appeals process, splashing out more than 150m euros (£117.5m) on Suarez, Ivan Rakitic, Marc-Andre ter Stegen, Thomas Vermaelen, Claudio Bravo, Jeremy Mathieu and Alen Halilovic.