FIFA have issued registration bans to seven clubs in a single day - including one that played in the Europa Conference League two years ago.
The bans can be applied in a range of different ways, including full player registration bans, transfer or loan embargos or fee restrictions.
There have been various cases in English football this season, with Championship side Hull restricted to signing free agents after their failure to pay off transfer debts.
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Crisis-hit Sheffield Wednesday, meanwhile, can only sign players as long as they make no payment towards the deal.
Their only summer signing was Manchester United defender Harry Amass on loan, with United covering the entire cost of the move including Amass' full wages and living arrangements in Yorkshire.
There are many more lesser-known cases around the world of clubs receiving registration or transfer bans from FIFA.
As per FIFA's Registration Bans List, world football's governing body was particularly busy on Thursday, with eight new entries on the ban list.
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Among those who have received registration bans are Turkish club Adana Demirspor, who played in the Europa Conference League qualifying rounds in the 2023/24 season.
They were relegated from the Turkish top flight last season due to financial irregularities, and have received a 18-point deduction this season in the second tier.
Adana have drawn one and lost seven of their opening eight matches, conceding 31 goals, and are already 25 points from safety.
Gibraltarian side Lynx FC are one of three other European side to have received a registration ban, alongside Latvian club FK Tukums and Turkish outfit Eyupspor, formerly managed by ex-Barcelona midfielder Arda Turan.
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The remaining clubs on the list are from South America, Africa and Asia, with Alfonso Ugarte (Peru), Khaleej Sirte SC (Libya) and Mohammedan Sporting Club (India) all receiving bans.
FIFA does not detail the exact reasons behind the registration bans and whether they are for administrative issues - where the suspension is normally lifted as soon as the issues are resolved - or for more serious matters.
Two of the listed clubs - Eyupspor and FK Tukums - both have no time limit on their suspensions, while the other five clubs are all registration banned for the upcoming three windows.
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Earlier this year, four Welsh clubs - Penybont, Pontypridd United, Colwyn Bay and Newport County - were all placed on FIFA's Registration Ban list.
In the case of Newport, who play in the fourth division of English football, their ban resulted from failure to pay a compensation fee to another EFL club for an academy player, which the club said had already been paid.
Out of the four clubs, only Penybont remain on FIFA's list.
Topics: FIFA, Transfers, Football, Europa Conference League
Ryan Smart