Answer:
Not allowed, FINRA prohibits private securities transactions. Trading must be done with the knowledge of your firm in the public securities markets
Step-by-step explanation:
Since in the question it is mentioned that call of the customer registered the representative for selling off 500 shares over the counter stock and the transactions should be done in privately
here according to the FINRA, it prohibits the transactions in which the person deals in private securities also there should be knowledge in the firm for the securities market held in market