Netting sets
Table of Contents
- 1. Summary
- 2. Detail
- 3. Sources
- 4. See also
1. Summary
A netting set is the group of trades with one counterparty whose values may legally offset one another when credit exposure is computed. Whether two trades can offset is a legal question: it needs a netting agreement, legal opinion that the agreement is enforceable, and, in the firm's own credit practice, the two trades falling under the same credit limit.
Exposure, credit line utilisation and collateral are all computed per netting set, and nettable and non-nettable trades are aggregated by different formulas. In the vocabulary of trade sets, groups and links it is a set: no operation attaches to its trades as a whole, and every trade belongs to exactly one. The identity behind it is the netting set itself, which carries the agreement and the collateral terms that govern its members.
"Netting" also names three operational mechanics — deal netting, expiry netting and settlement netting. None of them is a netting set, and the last section keeps them apart.
2. Detail
2.1. The legal basis
2.1.1. Master agreements
The market-standard documentation for OTC derivatives is the ISDA Master Agreement: one master document setting the terms for every derivative transaction between two parties, tailored by a Schedule of elections. It covers payment obligations, representations, events of default and termination, settlement on default and termination, and the netting of payments. Other agreement families sit alongside it, such as the French AFB and FBF agreements, and each has to be signed off as nettable before trades under it can offset.
2.1.2. Netting agreements and close-out netting
A netting agreement is a legal document that allows the parties to aggregate the amounts each owes the other under it and replace them with a single net amount payable by one party.
The reason it matters is default. Without enforceable netting, a firm whose counterparty defaults must pay on its out-of-the-money trades and lodge a claim for its in-the-money trades. With close-out netting, every contract between the two parties terminates on default and only the net amount is claimed or paid.
Trades are non-nettable when no netting agreement is in place, or when legal opinion advises that netting is not enforceable in the relevant jurisdiction.
2.1.3. Sign-off granularity
Nettability is not one yes or no per counterparty. The sign-off of an agreement as nettable can differ by contract type and by dealing centre, and collateral additionally needs a valid collateral netting option for the jurisdiction.
2.2. What determines a netting set
| Dimension | Rule |
|---|---|
| Counterparty | Netting is bilateral, so a set never spans counterparties |
| Legal entity | A set belongs to one legal entity on the firm's side |
| Netting agreement | Every trade in the set is eligible under the same agreement |
| Enforceability | The agreement is signed off as nettable for the trade's contract type and dealing centre |
| Credit limit | Where one agreement covers trades under several limits, netting is restricted to the trades within one limit |
| Trade eligibility | Some trades are carved out whatever the agreement says |
One counterparty may therefore have several netting sets, one per agreement and limit, plus a residual population of non-nettable trades.
Two kinds of trade never net, even inside an agreement. A trade overwrite — a manually entered flat exposure profile for an exotic or a product with no valuation model — is a single positive value and is carved out of any netting agreement; it can apply to an atomic trade or to a structure. A gross add-on for an intraday trade is floored at zero and added on, so it does not net either.
A netting set is not a book. Books are an internal risk-management construct; a netting set is a legal and credit grouping that cuts across books.
2.3. How netting changes exposure aggregation
Counterparty exposure is built from trade-level values per simulated scenario and future time point (a grid point), aggregated up to the counterparty. Nettable and non-nettable trades take different paths.
| Population | Value at a grid point, per scenario |
|---|---|
| Nettable trades in one set | max(MtM_1 + MtM_2 + … + MtM_n, 0) |
| Non-nettable trades | max(MtM_1, 0) + max(MtM_2, 0) + … + max(MtM_n, 0) |
Repeated over every scenario, the values form a distribution per grid point, and its percentiles give potential future exposure. Offsetting inside a netting set lowers that exposure relative to the sum of each trade's own exposure.
The same split survives every methodology. Scenario-consistent aggregation sums like shifts of like risk factors inside a set and floors non-nettable values first. Credit line utilisation keeps the netted and non-netted figures separate, and adds trade overwrites after both. An intraday trade booked between full runs is handled by a gross add-on: its floored exposure is added to the counterparty's profile, so it earns no netting benefit until the next full run.
2.4. Netting and collateral
A Credit Support Annex (CSA) is an optional part of an ISDA Master Agreement that regulates collateral. It sits on top of netting: netting reduces exposure, and collateral mitigates what remains. The firm's practice requires a separate CSA for each counterparty limit, which matches the agreement-and-limit granularity of the netting set.
Collateral exposure is portfolio-based: one threshold, one minimum transfer amount, and one collateral valuation per collateralised portfolio. A trade qualifies for collateral only when its agreement is signed off as nettable, its jurisdiction has a valid collateral netting option, and its contract type is in the permitted list. Non-nettable trades, excluded contract types and trades whose netting agreement does not match the collateral agreement are treated as uncollateralised.
2.5. How ORE represents a netting set
ORE is the ground truth for what can be priced, so its shape constrains ours.
- On the trade. The trade envelope names its netting set in one of
two forms.
NettingSetIdis a plain identifier.NettingSetDetailsis a composite: aNettingSetIdtogether withAgreementType,CallType,InitialMarginTypeandLegalEntityId. ORE therefore already treats the agreement type and the legal entity as part of a netting set's identity. - As a definition.
nettingsetdefinitions.xmldeclares each netting set once. A definition carriesActiveCSAFlagand, when the flag is set,CSADetails: whether the CSA is bilateral, the CSA currency and index, the pay and receive thresholds and minimum transfer amounts, the independent amount, the margining frequency, the margin period of risk, the collateral compounding spreads, the eligible collateral currencies, and the initial margin settings. - Balances.
collateralbalances.xmlstates the initial and variation margin held per netting set at the valuation date (see ORE model configuration).
ORE makes every trade name a netting set. A trade with nothing to net against sits in a netting set of its own.
2.6. What follows for the model
This section is analysis rather than reported practice.
2.6.1. Three entities, not one
The material above describes three things that a single "netting set id" column conflates:
| Entity | What it is | Identity |
|---|---|---|
| Netting agreement | The legal document between two legal entities | Agreement number; type (ISDA, AFB, FBF and so on); the two parties; governing law |
| Netting set | The trades that offset under one agreement within one limit | The agreement, the limit, and the ORE details: call type and initial margin type |
| Credit Support Annex | The collateral terms attached to a set | The agreement and limit it serves; it carries the CSADetails terms |
The agreement is the legal fact; the netting set is the credit grouping the agreement makes possible; the CSA is a term sheet attached to the set. They are modelled as ores.refdata.netting_agreement, ores.refdata.netting_set and ores.refdata.csa, with the CSA's eligible collateral in ores.refdata.csa_eligible_currency. Each has a lifecycle of its own: an agreement is signed, amended and terminated, a set is opened under it, and a CSA is added, changed or switched off without touching the trades.
2.6.2. Every trade belongs to exactly one set
Following ORE, membership is total: a trade always names a netting set. A non-nettable trade does not have an absent netting set; it belongs to a set whose agreement is missing or not enforceable, and the set says so. Nettability is then a property of the set, derived from its agreement's sign-off for the trade's contract type and dealing centre, rather than a flag maintained on each trade.
Because membership is total and a trade sits in one set at a time, it is a key on the trade's booking rather than a membership table.
2.6.3. Integrity the schema can enforce
- A set's counterparty and legal entity are those of its agreement.
- Every set belongs to a legal entity of the firm. The agreement number and the set code are unique within that legal entity, not across the tenant, because an agreement reference means something only between the two parties to it. Two legal entities may each hold an ISDA with the same bank under the same reference.
- A trade's counterparty and legal entity equal its set's. A composite key from the trade's booking to the set enforces this, so a trade cannot be filed in another counterparty's set.
- A CSA references exactly one set, and a set has at most one active CSA at a time. A CSA has the legal entity of its set. The insert trigger derives it from the set and ignores the party the caller sent, so the two cannot differ. A set shows only to the parties that can see its legal entity, so a session cannot file a CSA on another entity's set.
- An ORE netting set id names one set within a legal entity. Another legal entity may use the same id for its own set.
- Moving a trade to another set is a change to the trade's booking and is versioned with it. Re-papering — moving a population of trades to a new agreement — is a trade group with an identity, because an operation attaches to the population as a whole.
2.7. Not to be confused with operational netting
The word "netting" names three other mechanics. They share the word and not the legal meaning, and none of them changes a netting set.
| Kind | What is netted | Covered by |
|---|---|---|
| Deal netting | Client allocations or trades combined into one netted trade, with inter-desk transfers keeping each book's risk unchanged | Trade merge |
| Expiry netting | Expiring options combined into one net FX trade or one net cash flow | Trade merge |
| Settlement netting | All cash flows in one currency on one date paid as one amount | A payment mechanic; no trade changes |
The analysis notes also describe operational netting groups: sets of trades with a policy for expiry and settlement netting, possibly instantiated from structure templates. A netting group is not a netting set, and "non-nettable" in the operational sense — American digitals excluded from expiry netting — is a different attribute from "non-nettable" in the credit sense.
2.8. Open questions
- Is the limit part of the set everywhere? Restricting netting to one limit is a credit-limit choice rather than a legal one, and the notes do not say whether it is general practice.
- How is a trade assigned? The set could be captured at booking, derived from the counterparty, legal entity and product, or maintained by Credit. Derivation fits a closed rule best; capture fits exceptions best.
- What happens when sign-off changes? A change in legal opinion changes nettability for existing trades. Whether historical exposure is restated or only future runs change is not settled.
- Gross add-on conservatism. An intraday trade never reduces exposure until the next full run; limit breaches caused only by that are not discussed.
3. Sources
The legal basis, the aggregation formulas, the collateral rules and
the operational senses of netting are drawn from internal analysis
notes on netting sets, which summarise credit, collateral and
agreement material. The ORE representation is read from the ORE
schema: nettingsetdefinitions.xsd and the nettingSetDetails type.
The three-entity split, the total membership rule and the integrity
rules are this page's own analysis.
4. See also
- Trade — the structure note that orders this cluster.
- Trade sets and trade groups — why a netting set is a set whose identity is the netting set itself.
- Trade Modeling — the envelope that names a trade's netting set.
- Trade merge — deal and expiry netting, which share the word only.
- Risk Reporting — the reports exposure feeds.
- ORE model configuration — the collateral balances file.
- Knowledge — the hub of all knowledge notes.