What do banking regulations prohibit?

Answer: Bank anti tying laws

Explanation: Anti-tying statutes generally prohibit a bank from extending credit (or providing other services) to any person on the condition that the person also obtain some other product or service (other than certain traditional bank products) from the bank or an affiliate.

It gives the Federal Reserve the authority to regulate large banks before they become "too big to fail." It regulates hedge funds, derivatives, and mortgage brokers. The Volcker Rule bans banks from owning hedge funds or using investors' funds to trade derivatives for their own profit.