Apollo disclosed that the hackers accessed some of its cloud platforms between July 6 and July 10. The stolen information included names, home addresses, dates of birth and Social Security numbers.
The breach comes as Apollo has grown into one of the largest investment firms in the world. The company recently crossed $1 trillion in assets under management for the first time, reaching roughly $1.05 trillion after growing 25% over the past year.
Apollo said it is still investigating the attack and has not found evidence that the stolen information has been publicly released or used for identity theft. The firm is offering affected people free credit monitoring and identity protection.
The security problem arrives during a huge expansion under Rowan. Apollo generated a record $785 million in fee-related earnings during its latest quarter and arranged $74 billion of new financing and investments during the period.
The company is also moving deeper into managing money for individual investors and retirement accounts, making security especially important as Apollo handles both enormous amounts of capital and sensitive customer information.
Despite the breach, large investors have continued betting on Apollo. The number of hedge funds owning its shares recently increased from 74 to 81, as Rowan continues building a financial firm managing more than $1 trillion.