On what exchange does the data for these foreigners short selling appear.
It would seem without such data the short sells couldn’t be seen to have taken place, and would not impact a stock’s price.
In the example of Germany, there are smaller exchanges (ex. Berlin-Bremen Stock Exchange) around the country than the major bourse in Frankfurt, that have been caught listing U.S. securities without consent. And once listed there, a heavy increase in volitility, volume, and dramatic swings in stock prices can occur almost instantly.
Over 5,500 U.S. companies are listed on that exchange, with General Electric, Home Depot, Microsoft and most of their fellow Dow Jones Industrial Average components prominent among them, along with all Nasdaq-listed companies.
Listing a company without its consent is legal on Germany’s third market, called Freiverkehr, which in loose translation means “free traffic.”
A typical naked short sale scenerio on these exchanges will be:
The naked short seller will sell the stock and then buy it back quickly before the two-day window closes. That way, there’s never a need to deliver the securities or prove they were available.