On modified / nullified trades
You may have come across a transaction or two in your flow feed that is completely struck out:
Trades that have been struck out have been nullified (cancelled) or modified. Nullifications/modifications are a normal occurrence.
Unfortunately it is not specified if the trade in question has been outright nullified or if a modification has been made.
In this specific example we see, shortly after the nullification/modification, another trade on the same contract.
We can reason that in this case the trade was modified rather than nullified, given that we are seeing a similarly looking transaction on the tape.
As a reminder: as previously stated nothing explicitly states whether a trade has been outright nullified or if a modification has been made. If some flow you're tracking receives a red strike out make sure to pour over the flow feed to try and identify a modification. If no modification is visible then it's likely the trade was nullified.