Flash Surge in World’s Biggest ETF Linked to ‘Outlandish’ Trades

At 1:25 p.m. in New York on Monday, something unusual happened to the world’s largest exchange-traded fund.

After opening at $364.97 per share and straying less than 0.9% in either direction for almost four hours of trading, the price suddenly rocketed.

The SPDR S&P 500 ETF Trust (SPY) shot to $378.46, the highest level it has ever reached. More than 150,000 trades were executed at $370 or above, totaling almost $58 million. Then, just as suddenly, the price dropped back to about $367.50.

The whole thing took less than one second.

All times displayed are in London.

For any investor checking their portfolio at the ...