Derivatives Foundation interview preparation

Questions

100

Traced to a firm

29

Firms

19

Updated

September 2026

Asked at

All firmsMSMorgan Stanley4Nomura4Akuna Capital2Amundi2HSBC2PIMCO2Bank of America1Barclays1Citadel1DRW1Goldman Sachs1Jane Street1Millennium Management1Mizuho1Old Mission Capital1RCRBC Capital Markets1Scotiabank1UBS1Wells Fargo Securities1

Topic

All topicsForwards and futures10Options basics8Option pricing7The Greeks10Volatility7Option strategies9Swaps and rates7Credit derivatives4Market structure and clearing6Indian derivatives8Trading and markets9Brainteasers6Fit9

Level

AnyCoreIntermediateHard

Type

AnyTechnicalCaseMarket viewBrainteaserFit

1. 068What does prime brokerage do, and how does it connect to the derivatives business?Market structure and clearingIntermediatetechnicalMSMorgan StanleyGlobal Markets · London · 2024

   Say this

   Prime brokerage is the outsourced back and middle office for a hedge fund, plus the financing. It provides custody, clearing, consolidated reporting, margin lending, stock borrow for shorting, and synthetic exposure through swaps. It connects to derivatives because the synthetic financing business — total return swaps and portfolio swaps — is where much of the balance sheet and much of the revenue now sits.

   Then walk it

   1. The core services: execution and clearing across brokers, custody of assets, one consolidated report of positions and profit and loss, cash management, and capital introduction to help the fund raise money.
   2. The revenue is mostly financing. Margin lending on the long book, the spread on stock borrow for the short book, and fees on the synthetic side. Rebate on short sale proceeds is a bigger line than most people expect.
   3. Synthetic prime is the derivatives link. Instead of the fund buying the stock and borrowing money, the prime broker holds the stock and writes a total return swap to the fund. The fund gets the economics, the broker keeps the position and charges a financing spread. It is more capital-efficient for the fund and often cheaper than cash prime.
   4. That structure also has consequences the industry learned about the hard way. Synthetic positions are not disclosed as ownership in most jurisdictions, and because each broker sees only its own slice, a client can build enormous concentrated leverage across several primes. That is exactly what Archegos did in 2021, and it cost Credit Suisse over 5 billion dollars.
   5. The risk management question for the broker is margin methodology on a concentrated, illiquid book — and whether you have the client's full picture. A dynamic margin model that accounts for concentration and liquidation horizon is the difference between a profitable business and Archegos.
   6. For the fund, counterparty risk cuts the other way, which is the Lehman lesson: assets that were rehypothecated in the UK entity were part of the insolvency estate, and funds lost access for years. Which is why serious funds now run multiple primes, negotiate rehypothecation limits, and monitor where their assets actually sit.

   Where candidates lose it

   Reciting a service list. A Global Markets interviewer wants to hear where the money is — financing, not execution — and how synthetic prime uses derivatives. Naming Archegos on the broker's side and Lehman on the fund's side turns a description into an understanding of the risk.

   Expect next

   • Where does a prime broker actually make its money?
   • What is synthetic prime and why do funds use it?
   • What went wrong in the Archegos episode?

   Reported by candidates at Morgan Stanley (Global Markets, London, 2024). Source: Wall Street Oasis.

2. 069What makes the Indian index options market different from other major markets?Indian derivativesIntermediatetechnicalIndian derivatives desksIndian broking

   Say this

   Scale and concentration. By contract count India has been the largest derivatives market in the world for several years, and almost all of it is short-dated index options — Nifty and Bank Nifty weeklies — traded by a very large retail base. The premium turnover is a fraction of the notional, so the volume statistics flatter it enormously.

   Then walk it

   1. Structure: all index options are European and cash-settled on a weighted average price of the last half hour, which removes assignment and delivery mechanics entirely and makes the product very easy for retail to access.
   2. Lot sizes are set in notional terms and periodically revised, and SEBI raised them substantially in late 2024 specifically to make the minimum ticket larger and less accessible to small accounts.
   3. The expiry calendar is the defining feature. A weekly expiry means enormous gamma and theta concentration in the final days, and a very large share of total volume happens on expiry day itself in options that are almost entirely time value.
   4. Single stock derivatives exist but are a much smaller share, and they are physically settled since 2018 — which changed behaviour, because a retail trader holding an in-the-money single stock option now faces delivery obligations and much larger margins into expiry.
   5. Participants: proprietary and algorithmic firms dominate the profitable side, foreign portfolio investors and domestic institutions use index futures and options for hedging, and retail is overwhelmingly on the option-selling and cheap-option-buying side. The Jane Street enforcement matter in 2025 made the size of the prop share very public.
   6. The honest read: the volume numbers are not comparable to US or European markets, because a 50 rupee out-of-the-money Nifty option is one contract in the statistics and nearly no risk transfer. Premium turnover, not contract count, is the number to quote if you want to sound like you know the market rather than the headline.

   Where candidates lose it

   Quoting 'India is the world's largest derivatives market' as though it settles the matter. The comparison is by contract count, dominated by cheap weekly options, and premium turnover tells a different story. Making that distinction unprompted is the single best signal you understand this market.

   Expect next

   • Why is contract count a misleading comparison?
   • What changed when single stock derivatives moved to physical settlement?
   • Who is actually making money in this market?
3. 071Walk me through SEBI's margin framework and position limits for derivatives.Indian derivativesHardtechnicalIndian derivatives desksClearing and risk

   Say this

   Margin has two main layers: SPAN, which is the portfolio risk margin computed by the clearing corporation across scenarios, and exposure margin on top of it. Since 2020, margins are collected upfront and monitored at random intraday snapshots rather than end of day. Position limits are set separately for clients, trading members and foreign investors, in notional or open-interest terms.

   Then walk it

   1. SPAN margin: the clearing corporation revalues your whole portfolio under a grid of price and volatility scenarios and charges the worst case. It gives credit for genuine offsets, which is why a hedged spread costs far less margin than two outright positions.
   2. Exposure margin sits on top as an additional buffer, and short option positions attract specific additional requirements. Close to expiry, extra margins apply to in-the-money and near-the-money short positions because of settlement risk.
   3. The 2020 peak margin reform is the structural change worth knowing. Brokers must collect the full upfront margin, and compliance is checked against four random intraday snapshots each day, with penalties for shortfalls. That killed the intraday leverage brokers used to extend, which had been 20 to 50 times.
   4. Physical settlement in single stock derivatives compounds it: in the expiry week, margins on in-the-money single stock options escalate sharply, because delivery obligations arise. Retail traders regularly get caught by this.
   5. Position limits: client-level limits on index options in notional terms, market-wide position limits on single stocks expressed as a share of free float with a 95 percent trigger that bans new positions, and separate FPI category limits. Index option limits were tightened in 2025 with delta-adjusted rather than notional measurement, which was a direct response to the concentration issues the year before.
   6. Where the framework is genuinely good and where it strains: the upfront margin regime materially reduced client default risk and broker failures, which was the point. The strain is procyclicality and cost — margins rise into volatility, spreads widen, and hedging gets more expensive precisely when it is most needed. And measuring index option limits in notional rather than delta terms was an obvious gap until it was fixed.

   Where candidates lose it

   Naming SPAN and stopping. An Indian desk expects the 2020 peak-margin reform and the intraday snapshot mechanic, because it changed the whole broking business model. And the delta-adjusted position limit change is recent enough that knowing it marks you as current.

   Expect next

   • What did peak margin reporting do to the broking industry?
   • Why did SEBI move to delta-adjusted position limits?
   • How does SPAN give credit for a hedged position?
4. 073How do currency derivatives work on the Indian exchanges, and what are the constraints?Indian derivativesIntermediatetechnicalIndian derivatives desksFX derivatives

   Say this

   Exchange-traded currency futures and options on USD/INR and a few crosses, cash-settled in rupees against the RBI reference rate, with small lot sizes — a thousand dollars per futures lot. The defining constraint is that use is tied to having an underlying exposure: the RBI tightened enforcement of that in 2023 and effectively ended the speculative retail segment.

   Then walk it

   1. Products: USD/INR futures and options are by far the most liquid, plus EUR/INR, GBP/INR and JPY/INR futures with thin volumes, and cross-currency pairs like EUR/USD listed in rupee terms.
   2. Settlement is cash against the RBI reference rate on the expiry date, so there is no delivery of dollars. That makes it accessible but also means the contract is a proxy for, rather than a claim on, the spot market.
   3. Position limits are specific: a client-level cap on USD/INR positions, with larger limits only against demonstrated underlying exposure. The April 2023 clarification requiring participants to have a contracted exposure — and brokers to obtain that declaration — collapsed exchange volumes by a large multiple almost overnight.
   4. So the onshore exchange market is now mostly a hedging venue, and price discovery in the rupee happens elsewhere: the interbank OTC market onshore, and the non-deliverable forward market offshore in Singapore, London and Dubai.
   5. That NDF market is the thing to understand. It exists because the rupee is not fully convertible, it trades outside RBI jurisdiction, and it has repeatedly led onshore pricing during stress. The RBI's response was to let onshore banks participate in the NDF market from 2020, and to build the GIFT City IFSC as an onshore-offshore venue where rupee derivatives trade in dollars.
   6. The honest read on the market: it is small relative to India's trade flows because the regulatory framework prioritises controlling speculation over depth. That is a defensible policy choice — it limits the currency crisis channel — but it means a corporate hedging rupee exposure gets worse liquidity beyond a year than a comparable exposure in a freely convertible currency, and the difference shows up in the price.

   Where candidates lose it

   Describing the contracts without the exposure requirement and the NDF market. The 2023 underlying-exposure enforcement is the single most important recent fact about this market, and if you cannot explain why price discovery migrated offshore, you have described the plumbing without understanding the market.

   Expect next

   • What is an NDF and why does it exist for the rupee?
   • What changed for exchange volumes in 2023 and why?
   • How does GIFT City fit into this?
5. 074Why does Bank Nifty trade differently from Nifty in the options market?Indian derivativesIntermediatetechnicalIndian derivatives desksIndian broking

   Say this

   Because it is a narrow, highly concentrated sector index rather than a diversified one. Twelve banking names, with the top three carrying most of the weight, so it realises materially higher volatility than Nifty and its implied volatility sits several points above. That volatility difference is why it attracted the most aggressive short-dated option activity.

   Then walk it

   1. Composition: Bank Nifty is a dozen banking stocks with heavy concentration in the largest private banks. Nifty is 50 names across sectors, and financials are already its largest weight — which means the two indices are highly correlated but Bank Nifty is the levered version.
   2. Realised volatility runs perhaps 1.2 to 1.5 times Nifty's, and implied volatility follows, so option premiums are larger in both absolute and percentage terms. For a trader wanting the most movement per rupee of premium, Bank Nifty was the obvious instrument.
   3. It is also more event-driven. Credit policy, asset quality data, results from three or four large banks, and rate expectations all hit the whole index at once. Single-name news in HDFC Bank or ICICI moves the index in a way no single name moves Nifty.
   4. Consequence for the surface: skew is steeper and the term structure is more reactive, because a banking-sector shock is a credit shock and the market prices the left tail accordingly.
   5. The regulatory arc matters here. Bank Nifty weekly options had become the single largest contract in the world by volume, and SEBI's late-2024 rationalisation removed its weekly expiry, leaving the weekly to Nifty on the NSE. Volume redistributed rather than disappeared, but the Bank Nifty weekly ecosystem is gone.
   6. The trading implication I would draw: a Nifty against Bank Nifty relative-volatility trade is a clean expression of a view on whether financial-sector dispersion is going to rise. It is short correlation in one index and long it in the other, and it is a more considered trade than simply buying whichever premium looks cheap.

   Where candidates lose it

   Saying 'Bank Nifty is more volatile' without explaining the concentration mechanism, or missing that its weekly expiry was removed in the 2024 reforms. An Indian desk will assume you have traded it, so being current on the expiry change is the test.

   Expect next

   • How would you trade Nifty volatility against Bank Nifty volatility?
   • What happened to Bank Nifty weekly volumes after the 2024 changes?
   • Why is Bank Nifty skew steeper?
6. 076What does the Indian interest rate derivatives market look like, and why is it smaller than you would expect?Indian derivativesIntermediatetechnicalIndian derivatives desksRates derivatives

   Say this

   The liquid instrument is the overnight indexed swap against MIBOR, used mainly by banks and primary dealers to express rate views and manage their books. Bond futures exist and are thin, and the corporate swap market is small. The reason is that most Indian corporate borrowing is bank credit at a floating benchmark that resets anyway, so the hedging demand a deep swap market needs simply is not there.

   Then walk it

   1. OIS is the core. The overnight rate against MIBOR, liquid out to about five years and genuinely liquid in the one-year and five-year, and it is where the market's rate expectations are actually observable. If you want to know what the market thinks the RBI will do, you read the OIS curve, not the bond curve.
   2. Government bond futures on NSE and BSE exist but have never developed sustained liquidity, despite several relaunches. Banks hedge duration in the cash market instead, partly because the held-to-maturity accounting category removes the need to mark and therefore the need to hedge.
   3. Forward rate agreements and interest rate swaps with corporates happen, but the volumes are modest. Most Indian corporate debt is bank loans at a floating benchmark — previously the base rate or MCLR, now largely external benchmark linked — so companies are already floating and the treasurer's question is whether to fix, which many simply do not.
   4. The market also carries a legacy of caution. The 2008 to 2011 episode where corporates lost heavily on complex currency and rate structures sold by banks, and the resulting litigation and RBI scrutiny, made both boards and banks more conservative about derivative hedging than the economics alone would suggest.
   5. What is developing: RBI has progressively liberalised, allowing more participants into OIS and permitting banks to deal in offshore rupee derivatives, and the retail and non-bank participation frameworks have widened. The shift of benchmarks after LIBOR's end accelerated the use of overnight-indexed conventions.
   6. The honest structural point: a deep rates derivative market needs a liquid, marked, widely held government bond market, and India's is dominated by banks holding to maturity under statutory requirements. Until that holding structure changes, the derivative market will stay a bank-to-bank market rather than a broad hedging venue — which is the real answer to why it is smaller than the size of the economy implies.

   Where candidates lose it

   Assuming the Indian rates market mirrors the US or Europe. The interesting answer identifies the cause — statutory bond holdings, held-to-maturity accounting, and floating-rate bank credit — rather than just noting that volumes are low. Naming OIS against MIBOR as the real expectations curve is the practitioner detail.

   Expect next

   • Why have bond futures repeatedly failed to gain traction here?
   • Where would you read the market's view on the next RBI move?
   • What would have to change for the corporate swap market to grow?
7. 098When would you use C++ over Python on a trading desk?FitIntermediatetechnicalWells Fargo SecuritiesSales and Trading · Charlotte · 2026

   Say this

   C++ where latency and deterministic performance matter — the execution path, the pricing engine inside a market-making loop, anything in the hot path measured in microseconds. Python everywhere else: research, calibration, backtesting, reporting and glue. Most desks run both, with the Python layer calling into C++ libraries.

   Then walk it

   1. The real distinction is the hot path versus everything else. If code runs a million times a second between a market data tick and an order, you need C++ or something comparable — predictable memory layout, no garbage collector pauses, control over allocation and cache behaviour.
   2. Python's cost is not just raw speed, it is the interpreter's unpredictability. A garbage collection pause of a few milliseconds is irrelevant in research and fatal in a quoting engine.
   3. Where Python wins decisively: iteration speed in research, the numerical and data ecosystem, and readability for code that a team has to reason about. Pandas, NumPy and the scientific stack mean a volatility surface calibration takes an afternoon rather than a week.
   4. The standard architecture is both. Numerical kernels in C++ exposed through bindings, with Python orchestrating. The heavy libraries you use in Python are C or C++ underneath anyway, so a vectorised NumPy routine can be within a small factor of hand-written C++.
   5. So the practical answer: write it in Python first, measure, and only rewrite the part that is actually the bottleneck in C++. Premature optimisation in C++ costs weeks of development time for latency nobody was going to notice.
   6. And I would be honest about my own level. If I am stronger in Python, I say that and say what I have done in C++ — knowing enough to read a pricing library and understand why it is written the way it is, versus being able to write a low-latency engine, are different claims and I would not blur them.

   Where candidates lose it

   Answering 'C++ is faster' and stopping. The interviewer wants the hot-path distinction, the point that most production stacks are both, and the discipline of measuring before rewriting. And do not overclaim your C++ — a technical interviewer will test it in the next question.

   Expect next

   • What specifically would you put in C++ on a market-making system?
   • How fast can Python get if you vectorise properly?
   • How strong is your C++, honestly?

   Reported by candidates at Wells Fargo Securities (Sales and Trading, Charlotte, 2026). Source: Wall Street Oasis.

Firm tags come from public, anonymous candidate reports on Wall Street Oasis: strong signal, not sworn testimony. Firms are named as the places a question was reported, not as partners of Fin Maverick. Answers are written for this page to show how to think out loud; they are not scripts to recite.