I would say yes they do, for reference and research purposes check any 'change in significant holder' announcements, especially those involving the bigger investment banks. A number of these will lust all of the buy and sell trades along with the dates and amounts involved. It is after all the tried and tested way to average out your purchase price and leave you less exposed to market timing issues
NXT Price at posting:
$6.06 Sentiment: Buy Disclosure: Not Held
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