Peter Thiel, co-founder and chairman of Palantir Technologies (PLTR.US), recently sold nearly $600 million worth of company stock, bringing his total sales this year to more than $1 billion. The billionaire, through his investment firm Rivendell 7 LLC, sold more than 16 million shares of Palantir during the week, after having sold 20 million shares in March and May. Although regulatory filings did not disclose why Thiel sold the shares or how he would use the funds, the transactions underscored his confidence in the company's future. Mr. Thiel sold only Palantir's common stock, retaining shares with special voting rights, which ensured that he, along with co-founders Alex Karp and Stephen Cohen, continued control of the company's board of directors. Rivendell 7 LLC adopted a "10b5-1 rule plan" on May 15, allowing it to sell up to 28,590,737 shares by Dec. 31, 2025, according to Palantir's August filing. Thiel's most recent sale of Palantir shares was May 8-10, selling 13 million shares through a trading plan developed in December, with a total transaction volume of $273.5 million and an average selling price of $21.11 per share. Rivendell 7 still holds 62.9 million shares of Palanti after these deals