Archegos Capital Management, a hedge fund that collapsed earlier this year and cost multiple big banks billions of dollars, is reportedly the subject of an investigation launched by the Department of Justice.

Archegos owner Bill Hwang reportedly lost $8 billion over two weeks in March, when risky bets on ViacomCBS and several other stocks soured. The massive stock sell-off that followed caused billions in losses for some of Archegos’ largest lenders, most prominently Credit Suisse, which reported it lost $4.7 billion.

In the aftermath, the bank launched an investigation and parted with its chief risk and compliance officer.

Federal prosecutors in Manhattan sent requests for information to at least some of the banks that dealt with Archegos, according to a report Wednesday from Bloomberg News. It’s unclear what potential violations or entities authorities are examining, the report said.

Archegos’ meltdown has placed a spotlight on so-called family offices, which are not as tightly regulated by the Securities and Exchange Commission (SEC) and Commodity Futures Trading Commission (CFTC), compared to other investment firms. Family offices typically invest funds from wealthy families and individuals and do not accept investments from the public.

But while family offices may not pose a fraud risk to the average investor, a quick and total collapse of one can stress the market, as happened with Archegos. In addition, bank partners have less insight into the risky nature of investments made with money they loan to family offices. Regulators have already taken notice.

Both the SEC and CFTC are now exploring whether to revisit the family office exemption. The SEC has reportedly launched a preliminary investigation into the Archegos matter, while CFTC Commissioner Dan Berkovitz called for family offices to be regulated by the agency.

Berkovitz said under the Trump administration, the CFTC loosened notice requirements for family offices and also exempted those working for family offices from disclosing previous disqualifications.

“To protect the integrity of the commodity markets, the Commission must be aware of and able to monitor the activities of large family offices,” he wrote in a statement April 1. “In order to do this, the Commission should have basic information about family offices that are operating commodity pools. The qualifications of persons operating family offices should be no less than for persons operating other exempt and non-exempt pools.”