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A player is in an offside position if he is nearer to his opponents’ goal-line than the ball and the second last opponent (usually the last defender), unless he is in his own half. If the attacker is level, he is onside.
Most people also realise that a player cannot be offside from a goal kick, a throw-in or a corner, so now all we need to do is define when the offside position becomes an offence:
It is when, in the referee’s opinion, at the moment the ball is played or touches one of his team, a player is either interfering with play or an opponent, or gaining an advantage by being in that position.
The interpretation of those three points led to misunderstanding and inconsistent application and so the International FA Board made decisions which defined those criteria. They decreed that:
Interfering with play means playing or touching the ball passed or touched by a team-mate.
Interfering with an opponent means preventing an opponent from playing or being able to play the ball by clearly obstructing the opponent’s line of vision or movements or making a gesture or movement which, in the opinion of the referee, deceives or distracts an opponent.
Gaining an advantage by being in that position means playing a ball that rebounds to him off a goal-post or the crossbar having been in an offside position or playing the ball that rebounds to him off an opponent having been in an offside position.
So, unless a player touches the ball he is not interfering with play. It’s that simple and whether referees or assistants agree with that definition is irrelevant, they have to apply the law. Moreover, whether you or managers or pundits like it, that is how FIFA insist the offside law is applied.

thats the rule