Two Sigma Investments, one of the world's leading quantitative hedge funds, is laying off approximately 200 employees following a comprehensive review of its operations by its new Co-Chief Executive Officers, according to a report by Bloomberg.

The dismissals, representing about 10% of the firm’s 2,000-strong workforce, affect roles across corporate, engineering, modelling and trading, and securities departments. Portfolio managers were not included in the cuts, according to an unnamed Bloomberg source familiar with the matter.

The restructuring marks the first significant action by co-CEOs Carter Lyons and Scott Hoffman, who assumed leadership in September after the firm’s billionaire founders, John Overdeck and David Siegel, stepped down from day-to-day management amid escalating tensions.

Overdeck and Siegel, who co-founded the firm in 2001, remain chairmen and retain their equity stakes. However, their strained relationship led to a historic management overhaul, with the discord flagged as a material risk in a March 2023 regulatory filing — a rare disclosure for a hedge fund as secretive as Two Sigma.

The internal challenges have not derailed the firm's performance with its Absolute Return Enhanced Fund, the largest by assets, gaining 11.2% this year through mid-November, according to a source. Two Sigma’s total assets under management have reached a record $64bn.