Sam Bankman-Fried says he sometimes worked at the offices of the lawyers now investigating FTX after criticism of their past links

• Law firm Sullivan & Cromwell has been criticized for its involvement in FTX's bankruptcy having worked with the crypto exchange before.
• The firm described its relationship with FTX as "largely transactional" in a statement.

Sam Bankman-Fried said he sometimes worked out of the offices of the bankruptcy lawyers under fire for their past relationship with the crypto exchange, in a Substack post on Thursday.

An FTX customer filed a motion in the Delaware bankruptcy court on January 4, saying that law firm Sullivan & Cromwell couldn't properly investigate the collapsed crypto exchange due to their past relationship.

The filing, seen by Insider, says FTX paid the law firm $20.5 million before its bankruptcy, and FTX US's general counsel was once a partner at the firm.

Four senators, including Elizabeth Warren, then wrote to the judge overseeing the bankruptcy case to raise their concerns about Sullivan & Cromwell.

The judge, John Dorsey, criticized this intervention as "inappropriate," per CoinDesk. He added that the letter "will have no impact whatsoever on my decisions in this case, which will only be based upon the facts and law presented by the parties."

In a statement, the law firm said it "had a limited and largely transactional relationship with FTX."

In his Substack, however, Bankman-Fried contradicted that statement and described Sullivan & Cromwell as "one of FTX International's two primary law firms prior to bankruptcy," and "FTX US's primary law firm."

"FTX US' GC came from S&C, they worked with FTX US in its most important regulatory application, they worked with FTX International on some of its most important regulatory concerns, and they worked with FTX US on its most important transaction," Bankman-Fried wrote.

"When I would visit NYC, I would sometimes work out of S&C's office," he added.

On Substack, Bankman-Fried repeated his claim that he didn't "steal funds" from customers, and blamed the law firm for "strong-arming and threatening" him into naming bankruptcy veteran John J. Ray III as CEO.

He added that he believes FTX customers could have been reimbursed if it didn't file for bankruptcy.

On Wednesday, the court heard that SBF had a "secret" backdoor which gave his trading firm a $65 billion line of credit from customers' funds.

Andrew Dietderich, of Sullivan & Cromwell, told the court that line of credit was used to fund political donations and lavish purchases. Court filings show FTX owned $256.3 million of Bahamian real estate, and spent $6.9 million on "meals and entertainment" in nine months.

Dietderich added: "We know that all this has left a shortfall, in value to repay customers and creditors."

Sullivan & Cromwell did not immediately respond to Insider's request for comment, sent outside normal working hours.