Other than trying to hedge off any liabilities, is there any requirement to have any sort of disclaimer attached to outgoing emails from financial institutions? I know about the CAN-SPAM Act, and am not talking about email advertisements. My question deals more with run of the mill correspondences with customers, vendors, any other contacts.

I have seem some email disclaimers that say "federal law requires us to" disclose that this information is privileged, intended solely for the recipient, etc, etc. I have searched and could not find anything other than CAN-SPAM email advertising rules.

Technically, it should probably read "federal law requires us to... if we want to have a defense in court if sued while all the while reserving the right to sue you should you not hold this information to be confidential".

That said, if you want to forego your right to sue and expose your hind quarters, I am not aware of any regulation that says you can not do so.

No there is not. It is just CYA. One of those things we learned along the way.