Collingwood has been fined $20k for failing to register the details of an unlisted player who began training with the club late last year.
Before the player began training with the Pies, the club were meant to notify the AFL of the player's details, but failed to do so before he began.
AFL investigations manager Ken Wood found the Pies guilty of breaching the rules of list lodgement, and handed the club the $20,000 fine, although confirmed $10,000 of that will be suspended until October 31, 2018.
The League said the Magpies were happy to co-operate with the AFL during the investigation, with their co-operation taken into account when confirming Collingwood's financial sanction.