Nishad Singh, the former director of engineering at the failed crypto exchange FTX, pleaded guilty to U.S. criminal charges on Tuesday, according to Reuters.
Speculation mounted that Singh was working with U.S. prosecutors after Bloomberg reported in mid-February that Singh was planning to plead guilty. Last week, prosecutors filed superseding charges in their ongoing criminal case against FTX founder Sam Bankman-Fried, with new information about an individual described as “co-conspirator-1”—widely believed to be Singh.
Singh’s guilty plea comes after two other key lieutenants turned on Bankman-Fried: Caroline Ellison, the former chief executive at the FTX sister hedge fund Alameda Research, and Gary Wang, the former chief technology officer at FTX.
Prosecutors for the U.S. Department of Justice brought eight criminal charges against Bankman-Fried in December related to the collapse of FTX, where Singh held a crucial role in day-to-day operations. Bankman-Fried pleaded not guilty in December, and faces trial in October.
In December, Reuters reported that Singh made a secret change to the crypto exchange’s software that would exempt Alameda from automatically liquidating its assets if it were losing too much money, allowing it to continue borrowing funds.
According to a now-deleted FTX blog post, Singh was a close friend of Bankman-Fried’s brother in high school. He joined Alameda Research when it was a five-person trading firm based in Berkeley, Calif., before moving over to FTX.
When prosecutors unsealed their charges against Bankman-Fried in December, it was revealed that two of his former executives, Ellison and Wang, were cooperating with prosecutors and had agreed to plead guilty. Reuters later reported that former FTX top lawyer Daniel Friedberg also was cooperating.
The fate of other top FTX figures was left unknown, including Singh, former FTX co-CEO Ryan Salame, and former Alameda CEO Sam Trabucco.
The new charges filed against Bankman-Fried last week signaled that Singh was cooperating with prosecutors as well. Like Bankman-Fried, Singh was a prodigious political donor, giving millions of dollars to Democratic-affiliated candidates and political action committees.
The updated indictment included new insights into FTX’s political machine, with prosecutors alleging that Bankman-Fried had used “straw donors” to funnel donations using company—and customer—funds. The two straw donors were identified as FTX executives, and likely referred to Singh and Salame, due to publicly available campaign donation records.
A lawyer for Singh didn’t immediately respond to a request for comment from Fortune.
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