Tesla Motors announced Monday that is has acquired SolarCity for $2.6 billion. The oft-criticized move has been defended by Tesla CEO Elon Musk. Musk argued that the deal would accelerate Tesla's transition from electric-vehicle automaker into a better renewable-energy products company. SolarCity will get 45 days to seek an alternative buyer in a provision known as a "go-shop" period. Tesla shares fell 1.1% to $232.22 at 10:08 a.m., while SolarCity shares fell 4.5% to $25.51.