Volkswagen has pushed Amazon out of the top spot to become Rivian’s largest shareholder, new filings with the U.S. Securities and Exchange Commission show. VW Group’s increasing equity stake in Rivian, which has grown from 8.6% to 15.9% in less than two years, is tied to a joint venture with the EV startup. The Rivian and Volkswagen Group Technologies joint venture — officially formed in November 2024 — is focused on the development of electrical architecture and software. And that stake will continue to grow, as long as Rivian continues to meet its end of the deal. VW has committed to invest $5.8 billion into Rivian, capital that is unlocked as certain milestones are reached. The German automaker kicked off the deal with an initial $1 billion investment, followed by another $1 billion in mid-2025.…