Key Takeaways
- • Wooyoung Hong, a former quantitative researcher at Brevan Howard, filed a complaint in New York State Supreme Court (New York County) alleging that ex-portfolio manager Robert Sicari withheld up to $3.5 million in promised trading profits.
- • Hong claims Sicari promised him 50% of gains from certain trades and a 30% equity stake in ThirtyPark Capital, Sicari's newly launched fund, but later tried to renegotiate the deal in January.
- • Hong says the disputed trades, including bets tied to US Steel's acquisition by Nippon Steel, returned about 80%, entitling him to $1.2 million to $2 million on that position alone.
- • Sicari reportedly offered Hong a $400,000 cash payment plus a vesting 30% profit share; Hong says he objected, and was later cut off from firm systems and paid only $20,000 for his year at ThirtyPark.
- • Per Bloomberg, ThirtyPark is no longer operating, and Brevan Howard declined to comment.
Summary
Wooyoung Hong, a quantitative researcher who previously worked under Robert Sicari at Brevan Howard Asset Management, has sued Sicari over allegedly withheld trading profits, according to a complaint filed Tuesday in New York State Supreme Court, New York County, as reported by Bloomberg. The case is Hong v Sicari. Both men were dismissed from Brevan Howard in 2024, after which Sicari reportedly recruited Hong to ThirtyPark Capital, a fund Sicari was launching to invest his own capital.
According to the suit, Sicari promised Hong 50% of the gains from certain trades and a 30% stake in ThirtyPark. Hong estimates he is owed as much as $3.5 million for trades he handled between November 2024 and December 2025. He alleges the money was withheld to pressure him into renegotiating the equity portion of the arrangement. The trades cited include positions tied to CoreWeave's failed $9 billion takeover of Core Scientific, Chevron's acquisition of Hess, the Paramount Global-Skydance Media merger, and a bet on US Steel, which was then being acquired by Nippon Steel. Hong says the US Steel-related trades returned about 80%, which he calculates entitles him to $1.2 million to $2 million.
The complaint alleges that in January Sicari proposed replacing the original terms with a $400,000 cash payment and a 30% profit share that would vest over time, citing the need to conserve early-stage capital. Hong says he recorded calls in which Sicari questioned who was "eating all the commission" and asked him to work on "this percentage thing." Later that month, Sicari cut off Hong's access to firm systems, and Hong says he received only $20,000 for his year of work at ThirtyPark.
Reached by Bloomberg, Sicari said only that ThirtyPark is no longer operating and did not respond to follow-up messages; his lawyer declined to comment. Brevan Howard declined to comment. Hong's attorney, Juannell Riley, said, "In America, when you work, you should be paid." The allegations are unproven claims in a complaint.
According to the suit, Sicari promised Hong 50% of the gains from certain trades and a 30% stake in ThirtyPark. Hong estimates he is owed as much as $3.5 million for trades he handled between November 2024 and December 2025. He alleges the money was withheld to pressure him into renegotiating the equity portion of the arrangement. The trades cited include positions tied to CoreWeave's failed $9 billion takeover of Core Scientific, Chevron's acquisition of Hess, the Paramount Global-Skydance Media merger, and a bet on US Steel, which was then being acquired by Nippon Steel. Hong says the US Steel-related trades returned about 80%, which he calculates entitles him to $1.2 million to $2 million.
The complaint alleges that in January Sicari proposed replacing the original terms with a $400,000 cash payment and a 30% profit share that would vest over time, citing the need to conserve early-stage capital. Hong says he recorded calls in which Sicari questioned who was "eating all the commission" and asked him to work on "this percentage thing." Later that month, Sicari cut off Hong's access to firm systems, and Hong says he received only $20,000 for his year of work at ThirtyPark.
Reached by Bloomberg, Sicari said only that ThirtyPark is no longer operating and did not respond to follow-up messages; his lawyer declined to comment. Brevan Howard declined to comment. Hong's attorney, Juannell Riley, said, "In America, when you work, you should be paid." The allegations are unproven claims in a complaint.
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