Spent millions gathering? Two basic problems with that mindset. First, spending money to assemble a database of public facts does not magically give you a right to protect your investment in an uncopyrightable asset. Second, I don't know what millions you are talking about since craiglist's only asset is the users, and the users are just a result of tremendous network effects. They had a great idea and got very lucky, but gathering their massive userbase had nothing to do with spending money.