In the proposal, Buffett's Berkshire Hathaway Inc. BRK.A, +2.10% BRK.B, +2.23% would have provided a convertible loan that would have given the famed investor, significant exposure to potential upside in the ride-hailing giant, while limiting his risk, according to anonymous sources cited by Bloomberg News.
A representative for Mr Buffett did not immediately respond to a request for comment.
Berkshire had US$108.6 billion in cash and equivalents as of the end of March that it is eager to invest, Reuters noted. After Buffett's Berkshire Hathaway bought 75 million Apple shares in the first quarter the tech company's stock price rose by 4% in a single day, closing at an all-time high.More news: Kerr: Warriors got lucky after Smith error
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Uber is a technology company that, compared to Apple, is small and startup-y.
Buffett has recently struggled to find sizable attractive buys.
Uber is now in the middle of a fundraising spree ahead of the ride-sharing app's expected initial public offering, which is set to happen in 2019 and will doubtlessly be one of the biggest events in the market all year. I don't think we necessarily fit in with the typical Warren Buffett investment.
In the oast decade, Mr Buffett has invested billions of Berkshire dollars to support companies seeking a pick-me-up, including investments in Goldman Sachs Group, General Electric and Bank of America during or in the aftermath of the global financial crisis.
In February, Uber was valued at $72bn.
Many of these have carried favourable terms for Berkshire, giving it a reputation as a lender of last resort to companies in need.