George Soros Getty Images

But there is currently a mixed mood from investors toward Tesla. Shares are down nearly 9 percent year-to-date and at the end of March, traders were betting heavily against Tesla's bonds. The quarterly SEC filing does not give commentary as to why Soros' firm bought the Tesla bonds, but it gives a public insight into what the fund is buying and selling. The filing was released on May 15, 45 days since the end of the first quarter, so the positioning of the fund may have changed.

Amazon back in fashion