How does Intuit protect against card testing attacks?

Recently I was reading an article about someone who owns a small business and they fell victim to a card testing attack. This is where a card thief will automatically try and run thousands of transactions overnight through your merchant services account to find out which ones of the stolen cards are actually valid and working. The transactions can be as low as just a few cents, but with Intuit charging a transaction fee, plus the % fee for the amount charged if the card goes through. And in addition to this, if there are any necessary refunds, then that has a fee as well. If they successfully charge 2 million cards, at $0.25 per transaction, then that could potentially be $500,000 in the transaction fees alone. We monitor the bank account and merchant account throughout the day, but I'm feeling like this just isn't enough.

What does Intuit have set in place to protect us against this type of attack? And what can I do on my end with Intuit settings and such to help mitigate my risk of such an attack.