(Bloomberg) -- Marc Benioff’s cash pile grows a bit every day, thanks to a unique selling strategy unlike any other billionaire tracked by the Bloomberg Billionaires Index.

Since July, the Salesforce Inc. co-founder has been selling 15,000 shares of the software company’s stock — about $3 million worth — almost daily. Including a smaller selling streak earlier in the year, Benioff has unloaded more than $475 million worth of shares in 170 or so transactions.

His strategy of taking a little bit off the table every day dates to soon after Salesforce’s 2004 initial public offering, with Benioff making more than 200 sales the following year, records show. He’s continued the strategy since, which Benioff said helps fund charitable gifts to pediatric hospitals, public schools and medical research, among others.

“Business is the greatest platform for change,” Benioff, 59, said in a text message when asked about the stock sales. “This is why I love business because you can use it to improve the state of the world. That’s also why I love philanthropy.”

He also pointed to his ownership of Time magazine, a publication he purchased for $190 million in 2018.

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A chief executive officer selling hundreds of millions in stock can sometimes be a signal to investors or pose a legal risk, but Benioff’s approach is one of the “safest” ways to do it, said Alan Jagolinzer, a professor at Cambridge University’s Judge Business School. 

It’s important for CEOs and other executives to diversify and unload some of their shares, but they run the risk of violating insider trading rules or influencing the stock price if done all at once, he said. 

“That risk is significantly mitigated by trading every day because it subjects the sales to normal price movements,” Jagolinzer said. “Sometimes they trade advantageously and sometimes they don’t.” 

Zuckerberg, Bezos 

Other billionaires vary their stock liquidation approaches, from disposing of large blocks to taking years off from selling. Meta Platforms Inc.’s Mark Zuckerberg unloaded $185 million worth of shares in a series of transactions in November, his first sales in two years, while Amazon.com Inc. co-founder Jeff Bezos hasn’t sold any shares since disposing of more than $20 billion worth across 2020 and 2021.

After stepping down from Airbnb Inc. in 2022, co-founder Joe Gebbia has been offloading shares at a steady clip, including more than $1 billion worth by mid-July. The closest billionaire super-seller to Benioff is Morningstar Inc.’s Joe Mansueto, who has sold shares almost 100 times this year and about 1,500 times since 2006. Still, Benioff’s more than 2,800 transactions over the same period dwarf Mansueto’s.

Many executives and insiders file 10b5-1 trading plans to signal in advance they’re going to sell shares in a prescribed time window and certify that the sales aren’t based on material nonpublic information. The plans allow executives to sell in a predictable pattern, which can minimize spooking other investors. 

“The disadvantage is you can’t time things,” said Daniel Taylor, a professor at the University of Pennsylvania’s Wharton School, who researches CEO trading plans. “So if the stock price craters, you may be selling at a discount.”

That doesn’t mean the plans can’t be used strategically — as in the case of Salesforce’s leader. 

Benioff was selling 5,000 shares a day in 2020, but increased it to 15,000 daily in the last quarter of that year as Salesforce’s stock price climbed, according to data from InsiderSentiment.com, which tracks insider sales. As the market slumped in 2022, he reduced his sales and only offloaded a few thousand shares a day. But by July 2023, as Salesforce’s stock price rose above $200, Benioff again ramped up his selling to 15,000 shares daily.

“This is a very intelligently designed trading system, which helps Benioff sell his stock at above-average prices and avoids any danger in entangling with legal issues,” said Nejat Seyhun, a finance professor at the University of Michigan’s Ross School of Business, who analyzed Benioff’s trades on InsiderSentiment.

Benioff’s fortune has grown more than 55% in 2023 to $9.3 billion, according to the Bloomberg wealth index. He owns roughly 2.5% of the San Francisco-based company he founded in 1999, which makes up about two-thirds of his fortune with the balance in cash and other assets.

(Adds Joe Gebbia’s trades in 10th paragraph. An earlier version of this story corrected the spelling of Nejat Seyhun.)

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