This will decrease volume and liquidity for all plays. If you are stuck in a position that was once liquid and now is illiquid (like old high flyer) this will make selling more impossible. This is anti-free market model which is very unnatural and bad for true capitalism. These types of restrictions hurts retail as it will dramatically decrease liquidity.
And you want big retail ballers trading as that helps move a stock. Now the only big ballers that are allowed are the crooked mm's and promoters who don't use Penson anyway. All this does now is to make the true crooks (mm's, black boxes) even more powerful
How is this good news for you? How is lower liquidity a good thing? Subpennies will be even more dead now. You can't slowly accumulate a stock cause you're not allowed to due to volume constraints.
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