Amazon CEO Jeff Bezos sold 531,852 shares, or about 1% of his total stake, for $990 million, says Business Insider.
Bezos also donated another 268 shares — worth nearly $500,000 — to an unnamed nonprofit organization.
Earlier that same week, Bezos sold 965,612 shares, garnering more than $1.8 billion.
It's unclear why Bezos is selling stock and Amazon has declined to comment.
Investors usually consider sales by a CEO or other top executives at company to be a bad sign.