The Abu Dhabi Investment Council more than tripled the size of its position in a Bitcoin exchange-traded fund during the third quarter, shortly before the bull market in cryptocurrencies gave way to a brutal selloff. The firm, an independently-run unit of sovereign wealth fund Mubadala Investment Co., increased its holding in BlackRock Inc.'s iShares Bitcoin Trust ETF to almost 8 million shares as of Sept. 30, according to a regulatory filing. Bloomberg's Ben Scent has more on the story.