First off we use a simple actionscript to test the location of the movie.

var good_url:String = "http://www.yoursite.com";
var current_path:String = _url;
if (current_path.indexOf(good_url) == -1) {
    // bad location
	trace(_url);
    unloadMovie(_root);
}

The problem with this code is the thief could simply add a query string to the url and the check will be valid. Not exactly the result we are looking for, so on to a more in depth process of validating the location.

This other "better" option will be in a function that will return a true/false result on validation. We do this so the code can easily be reused over and over again.

function check_location() {
	// The good location
	var good_url:String = "http://www.mysite.com";
	// we add the correct domain as a query string, but notice it doesn't check out
	var current_path:String = _url + "/chocolate/chip/type?q=www.example.com";
	// now we pull apart the location to end up with a domain name piece
	var domain = current_path.substring(current_path.indexOf('http://') + 7).split('/');
	if(domain[0].indexOf(good_url) == -1) {
	    // bad location
	    unloadMovie(_root);
		return false;
	}
	return true;
}

if(check_location()) {
	trace("running on a good location");
}

As you can see this is a tougher check, but still suffers from the same limitation and that is Flash can be decompiled.

Well thats about it, now you should have a better understanding of how this all works.