London Traders Hit $500 Million Jackpot When Oil Went Negative (2)

On April 20 the price of a barrel of oil for delivery the following month plummeted $40 in an hour, settling at –$37. It was the first time crude had ever crossed into negative territory. Regulators, oil executives, and investors have struggled to understand how a commodity at the heart of almost every aspect of global trade had fallen so far that sellers had to pay counterparties to take it off their hands.

But for a small group of veteran traders at a tiny London firm called Vega Capital London Ltd., the mystery mattered less than the results: They pocketed ...