The Major League Soccer secondary transfer window is set to close on Wednesday night, ending the summertime period in which clubs can register new player signings.
Per FIFA regulations, MLS teams are able to request International Transfer Certificates (ITC) from players' former clubs to complete signings, loans and transfer deals during the transfer window. While deals can otherwise be completed outside the transfer windows, receipt of a player's ITC is required in order to add players to official rosters and for those players to be eligible to play in competitive matches.
The closing of the transfer window also means that the trade window within MLS for players will close.