Uber Technologies Inc. already is one of the world's most valuable companies, valued at as much as $120 billion, according to a report in The Wall Street Journal.

That valuation is based on recently received proposals from Wall Street banks Goldman Sachs Group Inc. (GS - Get Report) and Morgan Stanley (MS - Get Report) , sources familiar with the proposals told the Journal. 

If true, Uber is now valued at more than double what it was just two months ago. It would also be more valuable than legacy car companies General Motors Co. (GM - Get Report) , Ford Motor Co. (F - Get Report)  and Fiat Chrysler Automobiles NV  (FCAU - Get Report) combined. 

Also if true, Uber is by far the world's highest-valued, venture-backed private company. 

Uber has been one of Silicon Valley's biggest unicorns -- loosely defined as a privately held startup company valued at more than $1 billion -- since the ride-hailing company debuted nine years ago. 

Uber is widely expected to go public in 2019.

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