bigplayer said:
If they don't have your SSN and ID they will begin hounding you for it when you get close to 10K and then when you pass 10K if you don't give up the info you get barred from further play until you provide the required info and have a Suspicious Activity Report filed.
If you've been playing anonymously, they'll have no way to submit an SAR with your name or other identifying information on it. So if you're concerned about such things, play anonymously. I don't think that you want to attempt a buyin that will put you over $10,000 for the day--or even for a session spanning more than one day--unless you're prepared to give up the information. They WILL be keeping track of your buyins. Of course, casinos have been known to make mistakes in keeping totals, or even to have policies of demanding identification before allowing a buyin of somewhat less than $10,000, so you need to consider how you will handle it before pushing the envelope.
The end of a session during which you've refused to give identification is not a time that you want to cash chips at the cage. There's a big risk of the casino repeating the demand, or even of seizing your chips and refusing to relinquish them without identification. At which point your only remedy is to contact the regulatory authorities, who will in turn ask for your identification. So just walk out the door, and cash your chips a little at a time another day.