Definition

The International Swaps and Derivatives Association (ISDA) provides the legal backbone for the OTC derivatives market. The two core documents are:

Mechanism

By signing one Master Agreement, two parties can enter into multiple trades without renegotiating the core legal terms each time. In the event of a default, the agreement allows for the termination and close-out netting of all outstanding transactions into a single net payment.

Example

If Bank A defaults, the ISDA Master Agreement allows Bank B to terminate all trades, calculate a single net amount owed, and seize the collateral held under the CSA to cover that amount. This prevents a complex, trade-by-trade legal battle.

Day Count Conventions

These are rules used to calculate the amount of accrued interest over a period. Different markets use different conventions.

ConventionCalculationCommonly Used For
ACT/360Actual number of days in the period / 360Money markets, USD LIBOR/SOFR swaps.
30/360Assumes 30 days per month / 360 days a yearCorporate bonds, some swaps.
ACT/365 (Fixed)Actual number of days / 365UK Government Bonds (Gilts), GBP swaps.

Business Day Conventions

These rules adjust payment dates that fall on a non-business day (weekend or holiday).

Notional Principal

The notional is the theoretical principal amount on which interest payments and other calculations are based. It is a reference amount and is typically not exchanged, except in certain derivatives like cross-currency swaps.

Payment Frequencies

This defines how often payments are exchanged. Common frequencies for swaps are Quarterly (3M), Semi-Annually (6M), or Annually (1Y).

Roll Dates & IMM Dates

For many derivatives, payment and reset dates are aligned with standard "roll dates." The most common are the IMM (International Monetary Market) dates, which are the third Wednesday of March, June, September, and December.

Example

A 5-year USD interest rate swap with a quarterly frequency will have its payment dates aligned with the IMM dates for the next 20 quarters.

Definition

For floating-rate derivatives, the interest rate for a given period is "fixed" or "set" based on a published benchmark reference rate. This process is called a fixing or a reset.

Mechanism

The fixing typically occurs at the beginning of the accrual period (or with a small look-back of 1-2 days). The rate is taken from a designated source (e.g., the Federal Reserve Bank of New York for SOFR) and is used to calculate the floating payment for that period.

Example

An interest rate swap has a floating leg based on 3-month SOFR. For the period starting June 20th, the floating rate will be determined by the compounded SOFR rate over the preceding 3-month period, which is then published and used to calculate the next payment.

These are global standardized codes required for regulatory reporting to increase transparency in the derivatives market.

IdentifierStands ForPurpose
LEILegal Entity IdentifierA unique 20-character code that identifies a legal entity (e.g., a bank, fund, or corporation) involved in a financial transaction.
UTIUnique Transaction IdentifierA unique code assigned to each individual trade to track it throughout its lifecycle for regulatory reporting (under EMIR, Dodd-Frank, etc.).
UPIUnique Product IdentifierA code that classifies the derivative product itself, allowing regulators to aggregate data on specific types of instruments.

Definition

SWIFT is the global messaging network that financial institutions use to send and receive information, such as payment instructions and trade confirmations. There are two main standards:

Example

When a derivative trade is confirmed, the back office systems will automatically generate and send a SWIFT MT3xx series message to the counterparty. When a collateral payment is made, an MT202 (General Financial Institution Transfer) message might be used.

Summary Table

Convention/ConceptCore PurposeExample
ISDA Master AgreementStandardizes legal terms for all OTC trades between two parties.Enables close-out netting upon default.
CSA (Credit Support Annex)Defines the rules for collateral exchange (margining).Specifies eligible collateral and haircuts.
Day Count ConventionDetermines how interest is calculated for a period.ACT/360 for USD swaps.
Business Day ConventionAdjusts payment dates that fall on non-business days.Modified Following.
IMM DatesStandardized quarterly roll dates for many derivatives.Third Wednesday of Mar, Jun, Sep, Dec.
LEI / UTIUnique identifiers for entities and trades for regulatory reporting.Required under EMIR and Dodd-Frank.

Final Interview Tips

Be prepared to explain why day count conventions matter (they affect the exact cash amount of an interest payment). Understand the critical role of the ISDA and CSA in mitigating counterparty credit risk. Know what LEIs and UTIs are used for, as this demonstrates awareness of the modern regulatory landscape.