Nez I copied a line from the posting you had, basically it limits the amount of manipulation a stock can have. Have you ever put an order in at price seen multiple sales at your price and never been picked up? What was happening was the broker was buying shares and reselling them in front of customers and making a profit from it.
"Starting today, broker-dealers that handle customer limit orders in OTC equities, whether received from their own customers or from another member firm, cannot trade ahead of customer limit orders. This means that a firm cannot trade for its own account at a price equal to or better than a customer limit order without also executing the customer order."
This will only improve investors ability to move in and out of a stock and see a better picture of where a stock is on level 2 trading.
If you are a long term trader though it will have little impact in your trades though it benifits the momentum players more than anything else.
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