Naked Short Selling

Die amerikanische Börsenaufsicht SEC will das Spekulieren auf fallende Kurse, das so genannte "naked short selling" einschränken. Ab 21. Juli zunächst zum Schutz von 19 bestimmten Geldinstituten wie Fannie Mae, Freddie Mac, Lehman Brothers, Goldman Sachs, Merrill Lynch, etc...

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Naked short selling, or naked shorting, is the practice of selling a stock short without first borrowing the shares or ensuring that the shares can be borrowed. Naked shorting is not necessarily a violation of the federal securities laws, and can contribute to market liquidity, but is illegal when it drives down stock prices.

A large enough short sale could cause the price to fall, as is the case with any stock being sold, so as long as the trade is large enough to move the share price, the short is likely to be profitable. Normally this would be risky; if the price did move back up for other reasons, the trader would be driving the price up with every purchase, a condition known as a "short squeeze". (wikipedia.org)