Oh well, seems we are playin IP-Lottery now..
If one used thor or a vpn service: Screwed. Ip pool is very limited, so the chance of 3+ registrations with the same IP is very possible.
If your Internet provider does give you a new ip after reconnect (dsl/mobile) same thing. IP pool limited, next connect, someone else has the IP you had before.
You use things (in germany) like "freifunk" you are out of the game, limited IP pool.
Working in a company and sharing the IP with your co-workers.. very bad thing.
Using a Hot-spot : Bye bye.

I picked up, that there are 650.000 tokens left AFTER cleaning out the so called cheaters. Are you really telling me, that 65% of the accounts are fake accounts??
C'mon, that just can't be true! Again: Hooking the account to a IP is the most stupid thing to do! You CAN NOT identify a person by IP address! That's not how the internet is working!
This "3+ from the same IP" rule is just BS. There are so many other ways to handle this, like cookies, flash cookies and some other things (experts know, won't mention his now)
But just filtering by IP address is a thing for novices, you'll end up with exactly that, what's going on now: Shitstorm.

To make a statement here:
Me and 6 colleagues did promotion for Authorship. We sent mailings (with pictured instructions for the crypto newbies)  how to participate, how to set up a Wallet, how to register and so on.

All together we, 7 people, should have around 400-420 referrals. Yesterday we asked our refs in another mail if they received any Tokens yet.
Most stated: Account suspended (at the time the withdraw form was up) or for now, NOTHING received yet.
So what's going on? German IP's all got banned? Telekom, Vodafon, O2?
There's only 1 (ONE!) account from the 400+ (until now) that has been payed out.

Again, the 3 Ip rule is major BS, you also could do a "first letter of email is a V" rule.
I just feel sorry for the time we spent in supporting our list members, I know many of them also invested in the ICO (for that i have to say that the tokens arrived for everyone!)

Hint: Next time make the rules clear and precise before you start doing a campaign like this. Changing rules afterwards, when things have ended, is the much worst thing to do.