Castle Harlan's team of 18 investment managers has completed over 50 acquisitions since its inception with a total value of approximately $10 billion.

During the 60s John Castle headed all of the private equity activities, including the Sprout Capital Group, at Donaldson Lufkin & Jenrette (DLJ).

In 1987,[6] Castle and Harlan, with a few others raised $125 million for its new limited partnership, Legend Capital Group, L.P., to invest in leveraged buyout transactions.

CHAMP focuses on control investments in middle-market businesses in Australia and Southeast Asia with similar criteria to Castle Harlan.

[8] On April 17, 2018, Castle Harlan announced its agreement to purchase the oil and gas production equipment assets of Exterran Corporation.

[15][16] By November 2019, the firm had the following five investments: Sunless, Shelf Drilling, Caribbean Restaurants LLC,[17] Titan Production Equipment and Tensar Corp.[18] Since its launch, Castle Harlan has participated in the following eight private equity funds.