Welcome to WebmasterWorld Guest from 220.127.116.11
No Google ad or Google search box may be displayed on any domain parking websites, pop-ups, pop-unders, or in any email.
That means you just cant have adsense ads on pop ups or unders...but you can have actual pop unders with lets say a free screensaver ad?
Site may not include:
Pop-ups, pop-unders or exit windows that interfere with site navigation, obscure Google ads, change user preferences, or are for downloads. Other types of pop-ups, pop-unders, or exit windows may be allowed, provided that they do not exceed a combined total of 5 per user session