alt Hacker News> In fact, it’s unlikely such a list is even _allowed_ to exist given the sensitive nature of some areas of the business, being a publicly traded company which works directly with regulated entities and governments.
If the existence of a domain/subdomain is considered sensitive information, then something has gone very wrong.
Companies do register domains before launching products and don't want to leak them. Now, I still support Microsoft and other companies to list the domains they send official emails from.