February 19, 2010
Removing the uptick rule did 2 main things.
1) Increased volatility
2) Made it easy to build automated trading programs
On point one, it's a fact that volatility has increased and this is clearly bad for investors, but good for traders. Opponents of an 'Uptick Rule' say no uptick rule creates more liquidity. Liquidity at the expense of a fair, orderly market is liquidity we can do without.
On point two and this is a big one. The fewer rules in place, the easier it is to build models and trading programs (that work very fast). Being a former modeler, I would find it much easier to build a financial trading model in a world with no 'uptick rule' than in a world with one.
The rules that were removed over the past few years were put in place after the stock market crash to prevent another, and look what we got.
I ask you, is it considered manipulation if you buy and sell a stock with the intent to move the price of the stock instead of to take place in the movement of a stock?
Currently it's easier to manipulate stocks and just saying you can't short after 10% isn't good enough, as 10% is a large move.