Quote from mysticman:
Not sure I know what you mean here by "well below above fair value" and don't know where you get that part about legging in. I assume you are referring to buying the future first and then buying the option, but benysl said he would buy the option "immediately" upon buying the future. If the option market is open then these would be done at the same time and at fair value. However much of the time the option market may not be open so if the buy stop for the future is triggered overnight, he would have to wait to buy the option. See my suggestion below for avoiding this problem.
You do need the futures position if you want the collar. Just buying the option will not give you a collar, synthetic or otherwise. Looking at the call side for example, just buying the 1240 put is not enough. If you are thinking about establishing the short vertical synthetic collar, you would first have to buy the 1250 call back, then sell the 1250 put, and then buy the 1240 put. It would be much easier and cheaper to buy the future and the 1240 put. If outside of regular trading hours then you couldn't do anything with the options anyway, so the idea of a futures buy stop is good, simple, and effective almost 24/7. And we don't want to be putting in stops for options, right? The benefit of converting to the collar would be to cap the risk. Pretty straightforward.
My apologies, I assumed you were fully up to speed on synthetics hence the brevity in my earlier post.
Synthetics refresher:
Long futures + long PUT = long CALL OR
Long futures + short CALL = short PUT
As per your example, looking at the CALL side, instead of going long futures and long 1240 PUT, you can just buy the 1240 CALL. The futures position is not needed.
Collar:
Short 1250 CALL + long futures + long 1240 PUT
Depending on which substitution you wish to do, it is synthetically equivalent to:
Short 1250 CALL + long 1240 CALL (ITM Bull CALL vertical)
or even:
Long 1240 PUT + short 1250 PUT (OTM Bull PUT vertical)
i.e. the collar is a synthetic 1240/1250 bull vertical.
However, we already have the short 1250 CALL so let's stick with the bull CALL vertical variety.
What do I mean by legging in at greater than fair value?
We own the short CALL which is now showing a loss. We then buy the 1240 CALL (even if it is done synthetically with futures + PUT). Hence we have
legged into the bull CALL vertical and
own it for a price larger than if we were to buy the vertical outright at this juncture i.e. we have paid greater than "fair value" (read: market prices) for it. The difference between current market prices for the vertical and how much we paid for it is equal to the marked loss on the already owned short CALL.
MoMoney.