Apollo Global Management CEO Leon Black on Wednesday said during an earnings call that he made a "terrible mistake" by employing Jeffrey Epstein to work on personal financial and philanthropic services.

Why it matters: Apollo is one of the world's largest private equity firms, and already has lost at least one major client over Black's involvement with Epstein.

Black began the call saying that "it runs counter to my nature to speak publicly about personal matters," but believed he must because those matters are no affecting Apollo.

• "With the benefit of hindsight, working with [Epstein] was a horrible decision on my part."
• Black reiterated that Apollo never did business with Epstein. He also said that there is vetted documentation of the professional services provided by Epstein to Black and Black's family foundation, related to "estate planning, tax, structuring of art entities and philanthropic advice" between 2012 and 2017."
• Black explained that while he knew of Epstein's 2008 guilty plea in Florida for soliciting an underage girl for sex, he was led to believe Epstein had rehabilitated himself as evidenced by the "distinguished" people with whom Epstein associated.
• Black rejected any suggestion that he was ever blackmailed by Epstein, calling it "categorically untrue."
• He said that he wasn't made aware of the most "reprehensible" allegations against Epstein until "late 2018," even though many of them were reported on years earlier.

Black declined to take questions on Epstein from analysts, citing an investigation being conducted by law firm Dechert on Apollo's behalf.