What it means
A conventional collateral haircut might accept 80% of an asset's market value, whereas a portfolio risk-based calculation asks how the positions could change value across specified market moves. The resulting charge is tied to modelled loss rather than one percentage applied to every holding.
OCC describes its Risk Based Haircut methodology in connection with the US SEC net capital rule, using options pricing and portfolio theory for positions involving listed options. This is a particular regulatory-capital framework, not the rule for every loan or investment account globally.
The modelled portfolio can include eligible options, stocks, futures and options on futures, and eligibility matters because an economic relationship observed by a trader does not automatically earn an offset under the model. The methodology projects liquidation prices under a range of potential market scenarios, with inputs including the underlying price, volatility, interest rates and dividends, so changed inputs can change theoretical losses even when the number of contracts stays constant.
Within a class group, OCC describes offsetting one position's modelled gain against another's loss at the same valuation point, which is different from netting gains in a favourable scenario against losses in an unrelated adverse scenario. The portfolio must be assessed consistently at each point.
Additional product and portfolio groups can qualify for other offsets, but do not assume every related instrument cancels every other instrument's risk in full. The largest projected loss across the specified scenarios drives the described capital charge, with relevant minimum charges and other conditions.
A minimum can remain when offsetting positions show little market exposure, because liquidation risk does not disappear merely because a modelled hedge looks balanced. OCC makes theoretical profit-and-loss values available daily.
Capital charges and customer margin are related risk-management subjects but should not be treated as interchangeable labels. A broker's account requirement depends on the applicable rules and terms, so a manager should ask which calculation is being presented and what obligation it supports.
The model does not forecast the exact worst loss possible, since a market can move beyond its scenarios, liquidity can weaken or a supposed offset can diverge. The useful distinction for an owner is gross position, modelled net risk and available cash.
Increasing exposure simply because an offset reduced the charge can bring new risk back into the portfolio.
In practice
Real-world examples.
Example
A fictional portfolio contains an eligible underlying position and an offsetting option. At one modelled price move, one loses $150,000 and the other gains $100,000. The net modelled loss at that point is $50,000, before further framework requirements.
Example
Two instruments move similarly during calm trading but do not meet the model's offset criteria. The risk team does not grant a full capital reduction based only on historical resemblance.
Example
Operations removes one leg of a hedge. The remaining position's modelled losses rise, so the portfolio charge can increase even though gross holdings have decreased. Treasury reviews the changed requirement before the unwind.
Formula
Calculation
Simplified scenario net profit or loss = sum of eligible position profit-or-loss values at that same scenario, subject to permitted offsets.
In a fictional four-scenario illustration, combined results are a $50,000 loss, a $20,000 loss, a $10,000 gain and a $70,000 loss. The largest modelled loss is $70,000.
If the hypothetical applicable minimum were $80,000, the final charge could not be described as $70,000 simply by ignoring that floor; the charge would be the higher figure, $80,000. This reduced illustration is not OCC's complete calculation or its actual scenario grid.
A charge is not a realised trading loss. It is a requirement based on the method; actual liquidation results and account obligations need separate review.Case study
Seen in the real world.
Fictional case study: Ash Trading reports a lower capital charge after adding eligible offsets. Management initially treats the reduction as cash profit and proposes doubling positions. The risk team separates modelled charge from available liquidity and actual returns.
It also tests loss if the offset relationship weakens and checks the effect of closing either leg first. The review shows that portfolio recognition can improve capital use without removing settlement, liquidation or model risk. Management keeps exposure limits independent of the attractive net requirement.
Watch out
Common mistakes.
- Applying one collateral percentage and calling it the complete OCC portfolio method. Scenario-based capital treatment has additional mechanics.
- Assuming all hedges receive full offsets. Eligibility, grouping and minimum charges matter.
- Treating a smaller charge as profit or proof of a maximum possible loss. It is neither.
Questions
People also ask.
Is this just a collateral discount?
The phrase can be used broadly, but the OCC portfolio methodology calculates scenario-based capital charges.
Can a hedged portfolio still have a charge?
Yes. Residual exposure and minimum requirements can remain.
Does the modelled charge predict the exact worst loss?
No. It reflects a defined method and scenarios, not every possible market or liquidation outcome.
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