Credit Risk in Swaps

A swap, unlike a futures contract, is not guaranteed by an exchange. It's a private, bilateral agreement between two named counterparties — historically, most often, a corporation and a bank. If your counterparty goes bankrupt while your swap is sitting at a positive value to you, that value doesn't automatically show up in your bank account; it becomes a claim in bankruptcy court, standing in line behind secured creditors, worth however many cents on the dollar the estate eventually pays out. This is counterparty credit risk, and it is the single biggest structural difference between the over-the-counter (OTC) swap market and the exchange-traded futures market this course opened with.

What is actually at risk?

It's tempting to think the notional principal is what's on the line, but we established two lessons ago that a swap's economic value is its mark-to-market value — the difference of two bonds — not its notional. That value is exactly what's exposed:

\text{Exposure} = \max(V, 0),

where V is the swap's current value to you. If your counterparty defaults while V > 0, you lose up to that amount (less whatever the bankruptcy estate eventually recovers). If V < 0 — you owe them — their default costs you nothing; you still owe what you owe, and in fact you may come out ahead if a court lets you walk away from an above-market obligation. Exposure is one-directional: only the side who is "in the money" is at risk, and which side that is can flip back and forth over the swap's life as rates move.

Because a swap has years to run and interest rates wander unpredictably, the exposure isn't a single number — it's a whole profile over time, usually shaped like a hump: low near inception (rates haven't had time to move far), rising through the middle of the swap's life as more time has passed for rates to drift, then falling back toward zero near maturity (fewer remaining cash flows left to be exposed on).

Risk managers call this hump the expected positive exposure profile, and its peak — the single worst plausible loss over the swap's life — heavily informs how much a bank charges a client for entering the trade in the first place.

Netting: turning many exposures into one

A bank rarely has just one swap with a given counterparty; a large corporate client might have a dozen swaps running simultaneously against the same dealer, entered at different times for different purposes. Without any special agreement, each swap is legally its own separate contract — and in a bankruptcy, that separateness can be brutal.

Suppose a bank holds three swaps with Counterparty X, currently valued (to the bank) at +\$8\text{m}, -\$5\text{m}, and +\$3\text{m}. Without netting, each contract stands alone: the bank's exposure is the sum of only the positive ones, since a negative-value swap can't be used to offset a loss on a different contract —

\text{Exposure (no netting)} = \max(8, 0) + \max(-5, 0) + \max(3, 0) = 8 + 0 + 3 = \$11\text{m}.

A netting agreement — almost always an ISDA Master Agreement — legally bundles all swaps between the two parties into a single set of rights and obligations, so that on default the whole portfolio nets down to one number before anyone owes anyone anything:

\text{Exposure (with netting)} = \max(8 - 5 + 3, 0) = \max(6, 0) = \$6\text{m}.

Netting cut the bank's exposure to this counterparty from $11 million to $6 million — a 45% reduction — without a single new trade being done. This is why virtually no serious OTC derivatives relationship exists today without a signed master agreement in place before the first trade: the netting benefit is simply too large to leave on the table.

The International Swaps and Derivatives Association (ISDA) publishes a standard-form contract that two counterparties sign once, covering every derivative trade they'll ever do with each other. Rather than negotiating legal boilerplate from scratch for every single swap, the two parties negotiate the Master Agreement's terms once — including the crucial close-out netting language — and each individual trade afterward is just a short "confirmation" referencing it. Bolted onto the Master Agreement is usually a Credit Support Annex (CSA), which specifies how much collateral each side must post as the swap's mark-to-market value moves, refreshed daily — much like the margining you met on futures exchanges, but negotiated bilaterally instead of run by a clearinghouse. A well-drafted CSA can shrink the residual exposure this lesson has been computing down to nearly nothing, at the cost of both sides tying up cash or securities as collateral around the clock.

A netting agreement shrinks exposure from the sum of the positives to the net of everything — but the net can still be a large, uncomfortable number, as the $6 million residual above shows. Never describe netting as making counterparty risk disappear; it makes it smaller and more measurable, which is genuinely valuable but is not the same thing.

There is a subtler trap too: netting is a legal construct, and its enforceability depends on the bankruptcy law of the counterparty's home jurisdiction actually honoring close-out netting when a default occurs. In most major financial centers this is now well-settled law — but a bank trading with a counterparty in a jurisdiction where netting's legal status is untested or historically contested cannot simply assume the netted number is the real exposure; if a local court refuses to net, the position quietly reverts to the larger, un-netted sum, exactly when the counterparty is least able to make good on it.

From bilateral trust to central clearing

Netting and collateral manage counterparty risk between two specific firms, but they don't change the fact that every OTC swap ultimately depends on the two named counterparties' creditworthiness — and in the autumn of 2008, that dependency turned out to be a systemic problem, not just a bilateral one: thousands of banks were simultaneously exposed to each other through a tangled, largely invisible web of OTC swaps, and nobody — not regulators, not the banks themselves — had a clear picture of who owed what to whom. When one large, heavily-interconnected counterparty looked like it might fail, the fear wasn't just that one relationship would lose money; it was that the whole web might unravel at once.

The regulatory response, in the US (Dodd-Frank) and Europe (EMIR) alike, was to push large classes of standardized swaps toward mandatory central clearing — routing them through a central counterparty (CCP) exactly the way futures contracts have always worked, with daily margining, a mutualized default fund, and a single, transparent counterparty standing behind every trade instead of thousands of bilateral relationships nobody outside the two parties could see. It's the same insurance-pooling logic that makes futures exchanges safer than a purely bilateral forward market, applied retroactively to a market that had grown far too large, in the years since 1981, to keep running on counterparty-by-counterparty trust alone. We'll return to exactly this episode — and the wider cascade of failures it triggered — when the course reaches the 2008 financial crisis.