Here's what the law says
Law 11
It is not an offence in itself to be in an offside position.
A player in an offside position is only penalised if, at the moment the ball touches or is played by one of his team, he is, in the opinion of the referee, involved in active play by:
• interfering with play or
• interfering with an opponent or
• gaining an advantage by being in that position
In the event of an offside offence, the referee awards an indirect free kick to the opposing team to be taken from the place where the infringement occurred (see Law 13 – Position of free kick).
Now, to those who say it is where the player is standing when the ball is played to him, how do you mark the offence if two players run towards the ball, one from an offside position and one from an onside position? You are not to signal until the offence has been committed. In this situation, you cannot signal until the player who was in the offside position either plays the ball or his team mate gives up the chase. If he runs and then stops and team mate continues, but you have already signalled because you THOUGHT the player in an offside position was likely to get it, you are wrong in law. If he does commit the offences are you going to run back to the point where the player was when the ball was played or is it going to be where he committed the offence by becoming the most obvious player to play it?
Please tell me you aren't actually an assessor/tutor! The indirect free kick for an offside offence is taken from where the offending players was when the ball was last played to him by his team-mate.
Yes I am... please see my further comments below. Thanks for your thoughts
So if a player is in an offside position but commit the offense in his own half, the idfk for offside is in his own half?
In that situation you go back to where he became active, which is where he turns back into his own half to play the ball ... but this would still be in the opponents half
This was my next question. I was watching the scottish junior final and the referee gave the IDFK from the original position in the opponents half, rather than in his own half where he technically committed the offence.
Correct, see my post above