All volume is created by trades. All trades are a combination of a buy and a sell. Someone sells a stock to someone who buys. Classifying a trade as a buy or a sell usually depends on whether the trade went through on the buy or on the ask. In the gray and expert gray markets there is no bid. Buys and asks are not quoted. So it has no real value to classify a trade as a buy or a sell in the gray market. They are just trades. The only importance is the amount of volume, and the pps.
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