Citi is reportedly blocking debt deals with firms that kept the bank's accidental $500 million payout

• Citigroup is blocking investment firms that wouldn't return an accidental Revlon wire from future debt offerings led by the bank, according to a Bloomberg report.
• Citi accidentally transferred nearly $900 million to Revlon lenders last year when it meant to transfer only $8 million.
• A judge ruled last month that Citi can't recoup the $500 million 10 investment firms refused to send back.
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A botched debt repayment by Citigroup is now being used by the bank as reason to block certain investment firms from future debt offerings, according to a report from Bloomberg.

In what is considered to be "one of the biggest blunders in banking history," Citigroup accidentally sent nearly $900 million to Revlon lenders last year when it meant to only send about $8 million.

While some firms returned the money to Citigroup, others didn't, with 10 investment firms holding onto more than $500 million of the nearly $900 million accidental payment. A federal judge ruled last month that those investment firms do not have to return the money to Citigroup. Citigroup is appealing the decision.

Now, Citigroup is retaliating by blocking these 10 lenders from participating in certain debt offerings led by the bank, Bloomberg reported, citing people with knowledge of the matter. The investment firms targeted by Citigroup include Brigade Capital Management, HPS Investment Partners, and Symphony Asset Management, according to the report.

It's unclear whether the retaliation by Citigroup will be a big blow for the targeted firms, but it's hard to avoid Citigroup in debt markets given that it is one of the largest underwriters of new bonds and loans, according to Bloomberg.

However, the targeted firms can still participate in debt offerings led by Citigroup if the issuer specifically requests for their participation, Bloomberg reported.

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