Peter Thiel, the first major investor and a current board member at Facebook, has sold three-quarters of his remaining stake in the company, per Reuters. The move was part of a previously set trading plan, according to a filing document.

The backdrop: Thiel had already sold more than $1 billion worth of shares in Facebook before this most recent sell. He sold $640 million of stock in the company's IPO alone. A representative from Facebook told Reuters that the sale was routine and that Thiel continues to hold his seat on Facebook's board.