Switch to Desktop Site
 
 

Stocks stumble after a fake tweet announced White House attack

Stocks lost and then recovered on Tuesday after a false tweet announced an attack on the White House. In a matter of minutes, the stock market declined by one percent. 

Image

Glenn Kessler, right, works on the floor of the New York Stock Exchange last week. Stocks, which plunged briefly on a fake AP tweet, quickly recovered and then surged.

Richard Drew/AP/File

About these ads

For a few surreal minutes, a mere 12 words on Twitter caused the world's mightiest stock market to tremble.

No sooner did hackers send a false Associated Press tweet reporting explosions at the White House on Tuesday than investors started dumping stocks — eventually unloading $134 billion worth.

Except most of the investors weren't human. They were computers, selling on autopilot beyond the control of humans, like a scene from a sci-fi horror film.

"Before you could blink, it was over," said Joe Saluzzi, co-founder of Themis Trading and an outspoken critic of high-speed computerized trading. "With people, you wouldn't have this type of reaction."

For decades, computers have been sorting through data and news to help investment funds decide whether to buy or sell. But that's old school. Now "algorithmic" trading programs sift through data, news, even tweets, and execute trades by themselves in fractions of a second, without slowpoke humans getting in the way. More than half of stock trading every day is done this way.

Markets quickly recovered after Tuesday's plunge. But the incident rattled traders and highlighted the danger of handing control to the machines. It also raised questions about whether regulators should be doing more to monitor the relationship between social media and the markets.

Next

Page 1 of 5

Share