Back to OP,
LOTG Page 123:
"There are different circumstances when a player must be cautioned for
unsporting behaviour, e.g. if a player:
verbally distracts an opponent during play or at a restart"
If he says 'Mine' or 'Leave' to distract an opponent to leave the ball thinking its his team-mate wanting it (eg, goal kick hoofed long, red player behind blue player shouts 'Mine' and so blue purposefully leaves it thinking its a fellow blue) then, IDFK yellow for C1, but if its between 2 players on the same team, i tend to play on as its not distracting an opponent.