Google founders and controlling Alphabet stakeholders Larry Page and Sergey Brin have sold more than $1 billion worth of stock combined since May of this year.

Beginning in May of this year, the two sold both Class A and Class C shares worth more than $1.07 billion, according to filings with the Securities and Exchange Commission compiled by OpenInsider. Brin’s sales total more than $610 million, while Page’s sales — including a round this week — are now over $462 million. Both founders are selling under pre-filed trading plans.

Brin and Page last sold shares in 2017, when their last plan expired. The company’s stock has performed well this year — Alphabet Class A shares are up more than 50% year-to-date, outpacing the NASDAQ and the other tech giants (Amazon, Apple, Facebook and Microsoft). The company reported strong revenues and earnings for Q2 2021 on Wednesday as it rebounded from the worst effects of the Covid pandemic, including a 69% annualized jump in advertising revenue to more than $50 billion for the quarter.

At the end of 2019, Page stepped down from the role as Alphabet CEO, handing the reins to Google CEO Sundar Pichai. At the same time, Sergey Brin stepped down as president of Alphabet and his role was eliminated.

Page and Brin, who co-founded Google in 1998, remain board members and holding majority stake in the company, controlling 51% of a special class of Alphabet’s voting shares. The two are among the world’s richest people.

The reclusive Silicon Valley billionaires have kept a low-profile since stepping down from their leadership roles, although Brin made an appearance at Google’s first retail store in New York this week, CNBC has learned. Page has reportedly been spending a lot of time on his yacht in the Fijian Islands during the pandemic, according to Insider.

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