What's the Difference between Good and Bad Regulations?

According to L Gordon Crovitz - good regulation results in better and more useful information disclosure:

This public disclosure could bring the wisdom of crowds -- many investors processing information -- to a new area of the market. Information about equities makes stock markets highly efficient, with prices quickly reflecting accumulated knowledge among investors. Disclosure of derivatives positions could likewise help make forecasting more accurate for more esoteric topics like interest rates, foreign-exchange movements and corporate credit risk.