Depends on the broker. And OTC Markets has started to allow broker dealers to use OTCLink for “private” quotation for some grey market stocks that can help with liquidity. This does make it a little easier to trade.
But the ticking time bomb here is revocation. It comes without warning...and then the ticker disappears...no trading is even possible.
if tda bought the stock for you they can not refuse your sell order. they can however refuse to buy it for you. every brokerage has their own rules about what you may buy.
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