The rule would cap fees that customers are charged when they spend more money than they have in their bank accounts. Federal officials said large banks would have several options to comply. They could cap their overdraft fees at $5, or set their fees at another amount that covers their costs and losses. Alternatively, they could treat overdrafts as a line of credit and provide similar disclosures, including applicable interest rates.
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The rule would apply to institutions with more than $10 billion in assets, which includes about 150 of the nation’s roughly 9,000 banks and credit unions, and take effect in October.
So they just need to define the fee? Why not make it illegal to allow overdrafting?
It was already made illegal (as of mid 2010) without affirmative opt-in by the consumer.
https://www.consumerfinance.gov/rules-policy/regulations/1005/17/
Anyone who paid overdraft fees beyond August 15, 2010 affirmatively chose to do so.