A half tick at five digits would be hard to call. The two types of trades you would be looking for are a trade marked "avg" (under "type) during the day out to 5 or 6 digits or a t-trade occurring within minutes after close at some 5 or 6 digit price. If you take the price in either case, divide by .985 and see a resulting pps that fits either to an exact 4 digit price or is something between a set of previous existing trades then you are likely looking at a block sale.
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