Plenty on Wall Street love to hate active ETF big-guns like Ark Investment Management for having too much cash chasing too few stocks -- risking market distortions along the way.
Yet the relentless flood of money into exchange traded-funds means concentration risk is rising in some of the hottest corners of the passive world like climate-change investing.
This week overseers of the S&P Global Clean Energy Index took measures to combat the problem after recent record inflows into the likes of BlackRock Inc.’s $5.5 billion ETF (ticker