Bill Ackman, an early Coupang investor, donates his more than $1 billion stake to charity

Bill Ackman, founder and CEO of Pershing Square Capital Management.

Cameron Costa | CNBC

Billionaire investor Bill Ackman said Monday he donated his entire stake in Coupang — worth more than $1 billion — to charity following the South Korean e-commerce company’s IPO last week.

Ackman, who runs the Pershing Square Capital Management hedge fund, invested his personal money as an early backer of Coupang, CNBC first reported last Thursday on the firm’s NYSE debut.

Coupang, often called the Amazon of South Korea, saw its shares nearly double during its first trading day, before closing more than 40% higher. The stock was up around 5% to $51 on Monday, valuing Ackman’s gifted 26.5 million shares at more than $1.3 billion.

In a tweet Monday, Ackman said he was a “day one investor” in Coupang, which was founded in 2010 by CEO Bom Kim. Ackman said the Seoul-based company’s “incredible success” will now “benefit humanity.”

Ackman said the money — the breakdown of which was not disclosed — will go to three charitable organizations including his own Pershing Square Foundation.

According to its website, the PSF has committed over $400 million in “grants and social investments across a number of fields, including health and medicine, education, economic development and social justice.”

Source: CNBC