How is the 'side' of the trade determined in the flow?
The ‘side’ of the trade is determined by a few factors:
- the bid/ask of the contract at the time of the trade
- the trade price
Trades taking place at or closer to the NBBO Ask will be labeled ‘ASK’
Trades taking place at or closer to the NBBO Bid will be labeled ‘BID’
Trades taking place at the midpoint will be labeled ‘MID’