FINRA's Trusted Contact Rule
FINRA is the successor to the National Association of Securities Dealers, Inc. (NASD) and the member regulation, enforcement, and arbitration operations of the New York Stock Exchange. It is a non-governmental organization that regulates member brokerage firms and exchange markets.
The Trusted Contact Rule is not a POA, but allows financial institution to keep "trusted contact" information on file for one other person, besides the person named on the bank account. This is a person to ask if account activity seems suspicious.