Chelsea football club have been banned from signing players for the next two transfer windows and have been fined more than £460,000.
The ban will apply to signing players at both national and international level. It will not affect the Chelsea FC women's team.
Chelsea have said that they will appeal the ban. This could delay their punishment until after this summer's transfer window, meaning they could be free to make signings between the beginning of June and the end of August.
As it stands, Chelsea are banned from registering new players until summer 2020.
Fifa have also fined the Football Association £391,0000
The club was found guilty of breaking rules when signing and registering players under the age of 18.
Fifa investigated 92 transfers and found that the club broke regulations after 29 young players were registered incorrectly or illegally.
It is claimed that Bertrand Traore played 25 times for Chelsea at under-16, under-18 and first team level despite not being registered by the FA.
Chelsea can still sign players on loan and they can still sell players but they just can't sign any new players permanently.
This means that Gonzalo Higuain, who Chelsea signed on loan in the January transfer window, can be extended but not signed permanently.
According to Sky Germany, the recent transfer of Christian Pulisic from Borussia Dortmund to Chelsea should still stand as the transfer has already been confirmed.
The London club have announced that they disagree with Fifa's findings and will be appealing against the decision.
Fifa say there was no rules broken in the other 63 transfers they investigated.
Chelsea says that they are "extremely disappointed that Fifa has not accepted the clubs submissions in relation to the remaining 29 players".
Chelsea's decision to appeal will mean that the ban will not be enforced until after this summer's transfer window. That means the club could prepare for the worse and sign players until after the ban.
The FA also state that they will appeal against the decision.