Headquartered in Greenwich, Connecticut, Amaranth Advisors had $9 billion under management in its heyday. The firm, which was founded in 2000, claimed to employ a multi-strategy approach to investing that allowed “nimble portfolio managers to seize opportunities in whatever markets seem to be most promising at the time,” according to a 2006 New York Times article. In 2004, the hedge fund turned its focus to natural gas. The bet initially paid off: Amaranth made $1 billion in 2005 on rising energy prices. But in 2006, Amaranth lost more than $6 billion, leading to its collapse in what became one of the largest known trading losses of all time.