It won't affect anything. The MM's have been using time period from 4:00-4:15 as a catch all slot for making corrections ever since the got hit with mis-reporting their trade volume.If they fix an error before 4 they have to look up the specific code. Then mark it out of sequence. If its a broker/dealer/institutional buy, they may not want the traders to know, so display it after 4 and mark it with a "T".
After hours doesn't actually start till 4:15
There's a list of T&S codes in the Ibox. Up until recently if it wasn't a regular trade, they weren't recording it at all. The sec fined a couple MM's for doing that. So now even if it's just out-of-sequence, they give it a "T" wich makes it print at 4:00.
Basicly they're trying to confuse us
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