Soros Fund Management increased its bet on in the second quarter, albeit not through the more common stocks, after first buying in the first quarter.

US billionaire George Soros' Soros Fund Management increased its bet on Nio in the second quarter, albeit not through the more common stocks.

The fund held 51,317,000 Nio assets called "NOTE 2/0" at the end of the second quarter, up 19,417,000, or 60.87 percent, from 31,900,000 at the end of the first quarter, according to a Form 13F on Friday.

Unlike many other hedge funds whose positions are primarily in common stocks, Soros Fund Management's positions include a large number of alternative assets similar to these notes.

Assets labeled "Note" may be convertible senior notes of a company, and they are measured on Form 13F in "PRN", which stands for the principal amount on convertible debt securities.

Soros Fund Management first bought convertible notes of Nio in the first quarter of this year, and the latest data show that it increased its position in the second quarter.

The fund's holdings in Nio "NOTE 2/0" were valued at $43.9 million at the end of the second quarter, up 61 percent from $27.3 million at the end of the first quarter.

The fund also held Nio assets labeled "NOTE 0.500 percent 2/0", which numbered 71,896,000 at the end of the second quarter, up 2 million shares, or 2.86 percent, from 69,896,000 at the end of the first quarter.

The value of these "NOTE 0.500 percent 2/0" assets was $55 million at the end of the second quarter, a decrease of 3.6 percent from $57 million at the end of the first quarter.

Overall, the value of these Nio assets held by the fund increased by $14.6 million during the second quarter.

Soros Fund Management does not currently hold any assets in Nio's local peers Motors or .

Convertible notes, also commonly written as convertible bonds, allow holders to convert into shares of a company for a period of time in the future.

Typically, a company will pay holders principal and interest on convertible notes when they mature, if they don't convert them into shares.

On January 3 of this year, Nio notified holders of its 4.50 percent convertible senior notes due in 2024 that they would have the right to request that the company buy back all or a portion of such notes.

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