Nomura Holdings Inc.’s warning of a "significant” potential loss from an unnamed U.S. client is related to the unwinding of trades by Bill Hwang’s Archegos Capital Management, according to people familiar with the matter.

The family office founded by Hwang, a former Tiger Management trader, was one of Nomura’s prime brokerage clients, one of the people said, without providing further details. They asked not to be identified discussing private information.

Nomura said in a statement on Monday that the estimated amount of the claim against the U.S. client was about $2 billion.