August 18, 2009
short selling had NOTHING to do with the latest drop in the stock market. china had no short selling, no effect on their market. japan had no short selling for years, yet their market was stagnant.
if you're going to put in an uptick / test tick rule for short selling, put a similar downtick / test tick rule for long buying. it's inconsistent to have one without the other.
or, if you MUST have something on the books, do it as follows:
- if a stock has dropped 20% over several days AND
- has had a market cap of over (some number, say 200 billion)
THEN a test-tick rule can go in place.
after all, it's pretty obvious now that C, CIT, AIG, etc. were NOT brought down my short sellers, but my their terrible trading books.