Some of the sites here will give preferential listings to applications which are affiliated to their particular registration service. Some will only list such titles in their search results. If you want to be sure you don't miss any titles, then click through the categories and scroll through their list. We are not affiliated to anybody. If you want to check whether a site has a preferential system in place, then search for 'Pairs' and see if we are in the results list. Use these sites by all means. They have some great software. But if you're only using their search tools, don't assume that you've seen it all before making your decision to buy something.