The FTX Recovery Trust is trying to claw back $1.76B it says Sam Bankman-Fried fraudulently transferred to Binance in a July 2021 share buyback, and the defense is now widening discovery to FTX's best-known backers and chroniclers.

Binance Holdings and Changpeng Zhao seek records from "Shark Tank" host and FTX investor Kevin O'Leary, "Going Infinite" author Michael Lewis, a former Forbes digital assets research director and audit firm BDO USA. The notice was filed Wednesday in the US Bankruptcy Court for the District of Delaware, with subpoenas served last week.

The case covers $1.76B in BUSD, BNB and FTT that FTX paid to buy back Binance's stake, one of the largest clawback claims left in the FTX estate.

In July, Chief Judge Karen B. Owens let the core fraudulent-transfer claims proceed against four Binance entities and Zhao while dismissing other counts, so the case is now moving into evidence gathering.