What short selling restrictions exist in the U.S. that any investor with half a brain can't easily circumvent?corrections will always occur. the question is from what level. bubbles last longer where short sale restrictions exist.
the ultimate restriction is eliminating short selling altogether.
banning/limiting short selling when the market is falling is a different scenario altogether. under this scenario panic will ensue as traders/investors might envision closing of exchanges or restrictions on selling in general.