We track and filter on the number of shares traded - not trades. Although we do have an unusual print alert that might fit a derivative of what you are describing: http://www.trade-ideas.com/Help.html#UNOP
As for capping the number of alerts for a stock - that we can do. Put a value like 200 in the MAX Count filter and you won't see the 201st alert associated with the same stock. http://www.trade-ideas.com/Help.html#WSF_MinCount
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