What happens if use xyz.com when signing up for adsense then decide to remove the code from xyz.com but use adsense on a few other sites? Is your account closed by google? The other sites also contain content and are perfectly legal sites on which to place adsense ads. I removed the code from xyz.com because adsense was serving ads about topics I did not want to aid in promoting.
It dosent matter at all . Its your wish to retain or remove Ads on your sites untill and unless this comply with their policies
nothing will happen even if you remove all the code from all the sites, your account will still be valid and you can use it later on
That filter only filters on the basis of url. I want to filter ads on the basis of topic or subject. Is that possible?