But these wins were peanuts compared to the money made by a trader, or group of traders, who bought 420,000 September e-minis in the last 30 minutes of trading on June 28. That was some 40% of the day’s trading volume in September e-minis—making it a trade that could not easily be ignored. By then, President Trump was already in Osaka, Japan—14 hours ahead of Chicago—and on his way to a roughly hour-long meeting with China’s President Xi Jinping as part of the G20 summit. On Saturday in Osaka, after the market had closed in Chicago, Trump emerged from his meeting with Xi and announced that the intermittent trade talks were “back on track.” The following week was a good one in the stock market, thanks to the Trump announcement. On Thursday, June 27, the S&P 500 index stood at about 2915; a week or so later, it was just below 3000, a gain of 84 points, or $4,200 per e-mini contract. Whoever bought the 420,000 e-minis on June 28 had made a handsome profit of nearly $1.8 billion.

Traders in the Chicago pits have been watching these kinds of wagers with an increasing mixture of shock and awe since the start of the Trump presidency. They are used to rapid fluctuations in the S&P 500 index; volatility is common, of course. But the precision and timing of these trades, and the vast amount of money being made as a result of them, make the traders wonder if all this is on the level. Are the people behind these trades incredibly lucky, or do they have access to information that other people don’t have about, say, Trump’s or Beijing’s latest thinking on the trade war or any other of a number of ways that Trump is able to move the markets through his tweeting or slips of the tongue? Essentially, do they have inside information?…

There is no way for another trader, let alone an outsider such as me, to know who is making these trades. But regulators know or can find out. One longtime CME trader who has been watching with disgust says he’s never seen anything quite like these trades, not at least since al-Qaida cashed in before initiating the September 11 attacks. “There is definite hanky-panky going on, to the world’s financial markets’ detriment,” he says. “This is abysmal.”