Quote from Put_Master:
The swan could occur anytime during the contract, and the result would be 100% loss.... assuming it remained below your strike on expiration day
So bottom line is, if the stock dropped to 21, I would be at max margin with covered calls or have to sell about 10% of my theoretical shares..
But my account would not be 100% wiped out as in the case of the spread trader.
Or did I explain the theoretical example to them incorrectly?
But again, either way, the naked put seller is NOT wiped out. The spread trader is.
Or am I mistaken?
Thanks again for your response Put_Master. The answer to your question is: indeed you are mistaken.
Remember that this whole discussion centers around writing puts in a Reg T. (margin) account. We agree that cash secured puts are relatively safe. Perhaps that is where you are confused.
In any case, the best way to show how a naked put seller can wipe out his account is using a
real world example.
Take Facebook (FB) for instance. On July 18 2012, it closed at $29.11 (right there in the range you were suggesting). Lets say that just before the close you sold the Sept 25 Put. You collected in total a $1.05 premiun per contract (last close for that strike).
Also lets say that I sold the 25/23 Sept spread which at that same day and time fetched $0.45 (mid).
All those numbers can be cross-checked in any place you want.
So now, you and I have $100K to play around so you sell in total:
-400 FB Sep 25 PUT for $1.05
And I sell
-645 FB Sep 25/23 PUT spread for $0.45
The 400 and 645 are the number of contracts require to max out the $100K in our accounts respectively. So far we are fulfilling the terms of your example with a real world scenario.
Now, fast forward to July 31 2012, Facebook closed the day at $21.71 (right there in the "black swan" range), Now lets check our accounts.
The FB Sept 25 PUT is now at $4.10
The FB Sept 25/23 Put spread is at $1.40
Again those values are real quotes from the closing of that day.
With the values of that day the P/L for the naked put seller (you in this case) is of $-122000.00 (You were just wiped out).
In contrast, the P/L for the put spread is of $-61275.00 (I still have more than $38K in my account to play with).
As you can see the put spread is not wiped out right away, while the naked put seller is in a lot of trouble trying the find money to fulfill the margin calls or God forbid being assigned. I doubt the naked seller will survive for another day.
I hope that now you can see the real risk of selling naked puts in a Reg. T. account.