Tesla Motors (NASDAQ:TSLA) and SolarCity (NASDAQ:SCTY.DL) announced on Thursday that shareholders of both companies approved Tesla's acquisition of the solar company.

Tesla solar roof with a Powerwall and Model 3. Image source: Tesla Motors.

"Excluding the votes of Elon and other affiliated shareholders, more than 85% of shares voted were cast in favor of the acquisition," Tesla said in a Nov. 17 statement. Now that both companies' shareholders have approved the deal, Tesla expects the acquisition to close "in the coming days."

The deal will be an all-stock transaction, with SolarCity shareholders receiving 0.11 Tesla share for each SolarCity share they own.

Does it matter?

Acquiring SolarCity represented an important milestone for Tesla in its mission to create a sustainable future. With SolarCity under its own brand, Tesla will become the first integrated sustainable-energy company, selling energy generation, energy storage, and sustainable transportation products.

Tesla and SolarCity recently jointly unveiled a solar roof, or solar tiles that resemble high-end roofing options, which Tesla plans to bring to market under its own brand.

While there has been some debate as to whether or not SolarCity's business model will add or reduce risk to Tesla's business, the rock-bottom price of about $2 billion worth of Tesla stock the company is paying for SolarCity certainly helps mitigate any risk. Tesla is buying SolarCity stock after it fell about 60% from where it was trading three years ago.

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