Rule 108.3

A card's owner is the player who started the game with it in his or her deck. If a card is brought into the game from outside the game rather than starting in a player's deck, its owner is the player who brought it into the game. If a card starts the game in the command zone, its owner is the player who put it into the command zone to start the game. (Legal ownership of a card is irrelevant to the game rules except for the rules for ante; see rule 407.)

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