Bill Gates this week and last sold another 20 million shares of the company he co-founded, taking $752 million out of his shrinking Microsoft portfolio.
In four transactions between Feb. 12 and Feb. 18, Gates reduced his Microsoft holdings to just under 338 million shares.
Gates remained the largest single holder of Microsoft stock, but only by the slimmest of margins. Former CEO Steve Ballmer, who stepped aside earlier this month, currently owns 332 million shares. The share difference between the two long-time friends and business colleagues was only 4.7 million after Gates' selling spree.
Over the last decade, Gates has sold an average of 80 million shares annually, or 20 million each quarter, according to filings with the U.S. Securities and Exchange Commission (SEC), part of a plan to divest holdings in the company he and Paul Allen founded in 1975. Gates has pledged to give away the bulk of his wealth, with the Bill & Melinda Gates Foundation as a tool for that task.
Between Oct. 28 and Nov. 1. 2013, Gates sold 20 million shares worth $711 million, for example.
Gates' remaining shares were worth approximately $12.8 billion near the end of trading Friday.
With the 20 million shares sold this month -- likely the limit for the quarter -- Gates remained on track to hand over the crown to Ballmer in the next quarter, which ends June 30. Gates will have exhausted his holdings by September 2018 unless he stops or slows his selling, which he shows no sign of doing.
His dwindling portfolio was not the only change this month to Gates' position within Microsoft. On Feb. 4, the day Microsoft announced that Satya Nadella was its new CEO, Gates stepped down from the chairmanship of the board to become a hands-on advisor to Nadella on technology and product selection decisions.
Patrick Moorhead, principal analyst of Moor Insights & Strategies, described Gates' new role as consigliere to Nadella. "He'll be Nadella's advice guy," Moorhead said in an interview two weeks ago.
That change in titles, from Chairman to the longer Founder and Technology Advisor, was historic, Moorhead argued. "This is a milestone, an indication of not only a changing of the guard in Microsoft, but also a change in the technology business between the past and the future," Moorhead said.
So it will be when Gates runs out of his Microsoft shares.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is firstname.lastname@example.org.