Elon Musk' Tesla buys Elon Musk's SolarCity in a unifying bid to control sustainable energy and EV transportation industries. Elon Musk was a co-founder of SolarCity and sits on the board. He plans to acquire all of the outstanding shares of SolarCity's common stock in exchange for Tesla's common shares instead of paying cash. SolarCity was kinda of stumbling so it was relatively easier to acquire. The stock-swap is about 20-30% over today's SolarCity closing price. Their value at 2.7-2.8 billion dollars. Saving face or a family-friendly take-over.
https://techcrunch.com/2016/06/21/teslacity/