IB margin increase after close of market

[FSU]

Quote from 1245:

the market went up, vol went down. Your downside shock has changed.

OP stated that he had an iron condor in the SPX. If this is the case, a change in vol or a small change in the price of the SPX should have nothing to do with his margin. It should simply be his maximum loss on the on the spread (assuming the condor is within 20% of the current price of the index). There should be no change on the downside shock.

Correct me if I am wrong, 1245, as you understand PM better than I do.

 

[tradingjournals]

Quote from osho67:

I can live with IBs margin but to make big change after the markets have closed is really causes much worries. (26% increase is a lot)

I believe you could derive other conclusions from this -- conclusions that might be to your benefit.

 

[osho67]

Quote from tradingjournals:

I believe you could derive other conclusions from this -- conclusions that might be to your benefit.

I am not an expert as you are and I am a bit thick to understand. Please spell out what other conclusions might be to my benefit. You can send me p pm if you so prefer, Thanks- I must learn more.

 

[osho67]

Quote from FSU:

If you sold a 5 point iron condor in the SPX your maximum loss would be $500 (less what you sold it for). So if you sold the 1725/1730 put and 1800/1805 call condor for .30, your maximum loss would be $470 for every condor you sold. (This particular condor was the one that traded the most this week) Since a portfolio margin account is essentially a risk based account that looks up and down a certain percentage on the underlying index, I would not think the margin would be more than your expected loss.

I was trying to determine if the margin was miscalculated when you put the spread on originally or overnight. Either way I would not think that the margin should be more than your total possible loss and perhaps they are calculating incorrectly.

If someone else understands PM margin requirements differently, please chime in.

Say I have 70 iron condors positions all at 25 points, According to your calculation my maximum loss would be 175000 ( 2500X 70), The margin was at 80539 and it went up to 101245. So margin is still less than 175000, And now it has come back to 80539, So what do I learn from this?

 

[1245]

Quote from FSU:

OP stated that he had an iron condor in the SPX. If this is the case, a change in vol or a small change in the price of the SPX should have nothing to do with his margin. It should simply be his maximum loss on the on the spread (assuming the condor is within 20% of the current price of the index). There should be no change on the downside shock.

Correct me if I am wrong, 1245, as you understand PM better than I do.

The OCC shocks a portfolio. So if I'm short a vertical puts spread that is OTM, my expected loss down 8% is one number. If the SPX goes up 1 % the next day, my shock the next day will create a smaller loss. If the next day we are down 2 %, the following morning, my expected loss would be greater. PM changes everyday with new vols and new shocks. Condors are the same. Just easier to explain with a vertical. The shorter the time to expiration and further OTM, the less effect movement would cause with PM.

You can simulate this on the OCC website. create one position. Then create another with the strikes 20 SPX closer. This would simulate how margin would change, just without vol or date change.

http://apps.theocc.com/pmc/pmc.do

 

[osho67]

Quote from 1245:

The OCC shocks a portfolio. So if I'm short a vertical puts spread that is OTM, my expected loss down 8% is one number. If the SPX goes up 1 % the next day, my shock the next day will create a smaller loss. If the next day we are down 2 %, the following morning, my expected loss would be greater. PM changes everyday with new vols and new shocks. Condors are the same. Just easier to explain with a vertical. The shorter the time to expiration and further OTM, the less effect movement would cause with PM.

You can simulate this on the OCC website. create one position. Then create another with the strikes 20 SPX closer. This would simulate how margin would change, just without vol or date change.

http://apps.theocc.com/pmc/pmc.do

Thanks for OCC simulation info

 

[FSU]

Quote from 1245:

The OCC shocks a portfolio. So if I'm short a vertical puts spread that is OTM, my expected loss down 8% is one number. If the SPX goes up 1 % the next day, my shock the next day will create a smaller loss. If the next day we are down 2 %, the following morning, my expected loss would be greater. PM changes everyday with new vols and new shocks. Condors are the same. Just easier to explain with a vertical. The shorter the time to expiration and further OTM, the less effect movement would cause with PM.

You can simulate this on the OCC website. create one position. Then create another with the strikes 20 SPX closer. This would simulate how margin would change, just without vol or date change.

http://apps.theocc.com/pmc/pmc.do

Thanks for the more detailed comments. I had thought that PM just looked at max loss 20% down on indexes. I now see its not that simple. Interesting.

 

[1245]

Quote from FSU:

Thanks for the more detailed comments. I had thought that PM just looked at max loss 20% down on indexes. I now see its not that simple. Interesting.

The OCC shocks an SPX portfolio -8%/+6%. They only provide the vols and values after the close. Some time around 9pm ET most days. "ALL" (All as far as I know) prime brokers (PB) currently add house rules on top of that. Those house rules can change at any time. The PBs that don't want any tail risk, look up and down as much as 50%. 25% is more common. The lowest house rules that I know of right now are -15%/+10% for what they call unhedged SPX positions. The position this guy is discussing is hedged. But I still don't know how much this broker shocks for house rules.

One other comment. The way the OCC calculates Ivol tends to provide lower vols for OTM options. Using screen Ivols produce a higher requirement for short options. So the house rules are often more restrictive even for hedged positions because the risk department often uses screen vols during the day.