$35 billion hedge fund Millennium Management has hired a top trader from Citigroup

• Sebastian Ridd, who had been head of program trading and cash trading in the US at Citigroup, is joining giant hedge fund Millennium Management.
• His departure from Citigroup, along with that of global head of cash trading Armando Diaz,represents a shift at the top of the US bank’s stock trading business.

Millennium Management, the $35.7 billion hedge fund giant, has hired a top trader away from Citigroup.

Sebastian Ridd, head of program trading and cash trading in the US at Citigroup, left the firm in recent weeks and is headed to the hedge fund, according to people familiar with the matter.

It’s the second recent senior departure from Citi’s stock trading department. Last week, global head of cash trading Armando Diaz left the firm. Diaz had joined Citigroup from Millennium in 2016.

At Millennium, Ridd’s new role will entail working on the firm’s central risk desk, according to people familiar with the matter. Central risk operations serve as internal clearinghouses of sorts for trading firms to ensure they’re buying, selling, and hedging their trades efficiently.

Ridd could not be reached for comment. Citigroup declined to comment. Millennium declined to comment.