1: Whois every site on the list. 2: Did the owner information change since last time? 2n: No action required. Maybe select some sites randomly to have a human

1: Whois every site on the list. 2: Did the owner information change since last time? 2n: No action required. Maybe select some sites randomly to have a human compare, but it's probably fine. 2y: Have a human check the site. Did it simply get purchased by another (similar) organization, or is it no longer relevant to its original purpose? 3: Do the needful.