Defunct cryptocurrency exchange FTX has sold nearly $1 billion worth of shares in Grayscale's GTBC fund since the firm's instrument began trading recently as a spot bitcoin ETF, according to CoinDesk, which cited "private data" and anonymous sources.

Grayscale's spot bitcoin ETF has led rival funds in terms of trading volume, with much of that made up of outflows. As of Friday, Grayscale's fund had accounted for about 54% of trading volume since the new crypto-based ETFs began trading earlier this month, according to Yahoo Finance data compiled by The Block.

Bloomberg Intelligence senior ETF analyst Eric Balchunas posted data over the weekend showing that Grayscale's fund had shed $2.8 billion since trading began. 

FTX selling off shares in Grayscale's ETF is part of the failed …