Mark Zuckerberg has sold $296 million worth of Facebook shares in August

Facebook CEO Mark Zuckerberg at the F8 Facebook Developers conference on April 30, 2019 in San Jose, California.

Justin Sullivan | Getty Images

Mark Zuckerberg has been on a selling spree in August, unloading nearly 1.6 million shares of Facebook worth nearly $296 million.

Prior to this month, the Facebook co-founder and CEO hadn't sold shares since April. He's now sold 2.9 million shares this year worth more than $526 million. Zuckerberg still owns over 375 million Facebook shares with a current value of over $68 billion, making him the fifth-richest person in the world, behind Jeff Bezos, Bill Gates, Bernard Arnault and Warren Buffett.

Zuckerberg, 35, regularly sells parts of his Facebook fortune to fund the Chan Zuckerberg Initiative, the philanthropic organization he runs with his wife, Priscilla Chan. CZI funds programs in science and education as well as social issues focused on criminal justice reform, housing affordability and immigration reform.

According to the filings, Zuckerberg's share sales are part of a 10b5-1 plan, a rule established by the Securities and Exchange Commission that allows public company insiders to sell a predetermined amount of stock at set periods of time. Facebook's dual-class share structure allows Zuckerberg to retain voting control over the company's big decisions even as he sells a significant portion of his stake.

While his selling activity picked up in August, he's still well off the pace from last year, when Zuckerberg sold nearly 28.9 million shares for more than $5.3 billion. In late 2017, Zuckerberg said he planned to sell up to 75 million shares, worth more than $12 billion at the time, by March of this year.

Facebook shares were trading down by less than 1% on Thursday at $182.11.

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