MoMoney, thanks for typing these information. I know the sythetic relationship of the calls vs the puts position, but I don't know how IB is...
It is credit fly, just like qqqq 38/39/41 calls at +1/-2/+1 as an example. TOS would only charge margin on the 40/41 short vertical, but IB...
for ndx 1425/1475/1500 butterfly charges about $5000/spread on margin. IB is pretty stubbon and has no plan to change this. For the same...
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