Chelsea have lost their appeal to FIFA over the club's two-window transfer ban for breaching regulations relating to the international registration of players under the age of 18.
It is unclear which players are related to the breach of regulations.
Part of Chelsea's appeal was upheld, and the club will now be allowed to register players under the age of 16.
A statement from FIFA on Wednesday read: "With respect to all men’s teams, the ban on registering new players, both nationally and internationally for two registration periods, has been confirmed by the FIFA Appeal Committee, with the following exception:
"The FIFA Appeal Committee believes that Chelsea’s wrongdoing consisted in not respecting the prohibition from internationally transferring or registering for the first time foreign minor players.
"In the committee´s opinion, imposing a ban on registering each and every minor would not be proportionate to the offence committed.
"Consequently, the FIFA Appeal Committee decided that, as far as youth categories are concerned, the ban shall not cover the registration of minor players under the age of 16 who do not fall under the scope of art. 19 of the Regulations on the Status and Transfer of Players, which refers to international transfers and first registrations of foreign minor players."
Chelsea have responded to the decision, saying in a statement: "Chelsea FC has today received the decision of the FIFA Appeal Committee.
"The club notes that the FIFA Appeal Committee has decided to partially uphold the appeal lodged by Chelsea FC against the decision of the FIFA Disciplinary Committee. However, the club is very disappointed that the transfer ban of two consecutive registration periods was not overturned.
"Chelsea FC categorically refutes the findings of the FIFA Appeal Committee. It acted in accordance with the relevant regulations and will appeal the decision to the Court of Arbitration for Sport (CAS)."
Chelsea previously appealed to FIFA regarding the ban in the hope it would be delayed, but when the governing body refused in March, the club said it was "astonished".
Barcelona had successfully made a similar appeal over their transfer ban in 2014 which saw the prohibition postponed until the following year.
The Catalan club was then able to bring Luis Suarez, Ivan Rakitic, Jeremy Mathieu, Claudio Bravo and Marc-Andre ter Stegen to Camp Nou before the ban was imposed.
Their deal to sign Christian Pulisic, however, is not affected given the USA international was signed in January and loaned back to Borussia Dortmund for the remainder of the 2018-19 campaign.