Securities Amendment Act of 1975

Before 1975, trading stocks was very much a regional thing. New York was the sun, and the rest of the world more or less just orbited. The 1975 Act created a national market clearing system, so that a share of IBM traded for generally the same price in California, Georgia, New Hampshire, and New York.

This way, smaller, less-liquid regions weren't penalized with higher transaction costs than the wolves on Wall Street.

And that’s pretty much it. Basically, it was passed to ensure that the SEC would consider any new regulation that might come down the pike from that point forward, in terms of fairness and level-playing-field competition.

Fairness For The Win.