The mysterious 21% plunge in GE's stock

What the heck is going on with stocks?
What the heck is going on with stocks?

General Electric shares mysteriously plummeted 21% on Monday in the midst of the unprecedented 1,089-point plunge on the Dow.

It was a stunning moment for GE (GE), one of America's most iconic companies. An astonishing $53 billion of its value vanish in mere seconds -- before rapidly recovering nearly as quickly.

To put GE's 21% plunge into perspective, it was the stock's biggest one-day decline since the Black Monday crash of 1987.

The magnitude of the GE losses are striking because they far exceeded those of its peers and did not appear to be driven by any news specifically linked to the company.

A manufacturer of everything from jet engines to light bulbs, GE is a very large company, so it shouldn't be subject to violent stock market swings. Those moves, absent major news, are typically reserved for tiny companies, or high-flying stocks like GoPro (GPRO) .

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Pepsi plunged too. But not Coke

Yet GE wasn't the only giant stock violently tossed around by the dramatic market action. Pepsi (PEP) shares too briefly declined over 20%. By comparison, shares of rival Coca-Cola (KO) didn't fall more than 7.5%.

GE and Pepsi appear to be the highest-profile victims of the panic selling that crashed onto Wall Street on Monday. It's not yet clear why these two particular stocks fell as hard as they did.

Victims of a liquidity vacuum?

However, several market experts believe it was a function of extreme fear in the markets at that moment.

It created what's known as a "liquidity vacuum," where it becomes extremely difficult to trade a stock because of the lack of buyers. The situation can cause prices to swing dramatically, until a buyer finally emerges.

"At a time of maximum fear like that, nobody wants to step up to the plate," said James Angel, a finance professor at Georgetown University, who has testified before Congress about market structure issues.

The problem is that today's markets rely on such buying activity to come from high-speed traders, explains Dennis Dick, a market structure consultant at Bright Trading.

However, high-speed traders have been accused of disappearing when there's a very large move, such as Monday's.

Dick compared it with the May 2010 flash clash -- just at a far smaller scale.

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Trading halts didn't apply for GE

Selling was so dramatic on Monday that trading was automatically halted more than 1,200 times, according to Nasdaq. Yet most of those trading halts occurred in smaller, less liquid securities that are most vulnerable to the market's vicious moves.

Installed after the flash crash, these circuit breakers are designed to give stocks a time out and allow cooler heads to step into the market. They are triggered when stocks dive or spike by a certain amount in a matter of minutes.

Trading in GE and Pepsi was not halted because their declines occurred just after the opening bell. Circuit breakers don't go into effect during the first 15 minutes of the trading day nor in the final 25 minutes.

Will regulators act?

Luther Zhao, a research analyst at TABB Group, predicted Monday's events will be scrutinized by regulators and could even inspire new rules or changes in existing regulations.

Both GE and the Securities and Exchange Commission declined comment. Pepsi did not respond to a request for comment.

"The panic and lack of liquidity that largely contributed to the violent crash on the open rings many similarities to the flash crash in May 2010," Zhao wrote in a report.

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