Millennium Management is an American multi-manager hedge fund run by Israel Englander. Along with Citadel and Point72, it is one of the dominant multi-manager funds that have consolidated the active-investing industry.
Millennium is known for imposing tight risk limits on its portfolio managers, making it quicker to cut positions in a shock than peers like Citadel. Demand for its services has allowed it to raise capital that investors lock up for up to five years, far longer than is typical at hedge funds.
The firm is reportedly considering selling a minority stake in its business and has invested in other funds, most of them spin-outs of Millennium's own investment teams. According to Goldman Sachs, 40% of multi-manager funds now seed external managers in this way. Millennium is also expanding into private credit.
Jane Street sued Millennium after the fund hired two of its traders who had pulled off a particularly profitable trade in India.
In 2025 Millennium's index-rebalancing strategies lost hundreds of millions of dollars in two separate months when momentum reversed, snapping long winning streaks.
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