Former mayor of New York City Michael Bloomberg, who has kept his $60 billion media empire Bloomberg LP private since its founding in 1981, is reportedly in talks with hedge fund manager Bill Ackman to sell a minority stake. This according to a recent article in The New York Post.

Bloomberg LP generates revenue of $10 billion a year, the article reports, adding that Ackman could potentially buy a 20 percent stake for $12 billion to invest in his special-purpose acquisition company (SPAC). Although Bloomberg has long resisted taking his company public or diluting his 88-percent ownership stake, the proposed deal would allow him to cash out some stock without surrendering control.

Ackman befriended Bloomberg during the former mayor’s ill-fated presidential run, the article says. The proposed deal would allow Bloomberg to raise cash to meet the giving pledge that both he and Ackman have committed to—specifically, The Giving Pledge campaign founded by Warren Buffett and Bill and Melinda Gates that encourages billionaires to contribute the majority of their wealth to charitable causes during their lifetimes or in their wills.

The article notes, “Sources say Bloomberg LP has long been at the top of Ackman’s list of potential acquisitions, and Wall Street chatter over a potential deal picked up steam after Ackman’s approach to merge with Airbnb was reportedly rebuffed in August.”

For Ackman, the article says, “a merger with Bloomberg would be a huge win for his investors — giving them stakes in a major media company for $20 a share, which is what they paid for stock in the shell entity. It would also help cement Ackman’s transition from hedge fund manager to tycoon investor.”