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How To Trade VALE Unusual Options Activity
There are many ways to interpret UOA. Some common strategies include looking at the strike prices and comparing them to the current stock price for Vale Sa.
A bullish signal can be intrerpreted if you notice a large amount of contracts traded for strikes that are considered out of the money and expiring in the near future.
You can then compare the overall volume for that strike to the open interest at the beginning of the day.
A larger volume of option contracts traded compared to the open interest would mean this is a new position that is being opened.