Why Rivian Stock Dropped Thursday

Rivian Automotive (RIVN -5.74%) stock is hitting the brakes today after it spiked nearly 14% yesterday. That jump came after the company announced final terms for a joint venture (JV) with global automaker Volkswagen. But shares of the electric vehicle (EV) start-up were down by 5% today, as of 11:15 a.m. ET.Investors cheered the details announced with the closing of the JV yesterday. But the partnership had been previously announced, so today's drop likely reflects that fact, as well as uncertainty about R ...