Central clearing dampens repo specialness, stabilizes pricing in stress

Repo markets operate either bilaterally over-the-counter (OTC) or through central counterparties (CCPs).

A new ECB working paper develops a model showing that these structures have distinct pricing implications for security-driven repos.

In OTC markets, repo rates reflect borrower-specific risk, allowing lenders to condition prices on individual borrower identity.

Conversely, CCP markets pool counterparties, applying a common pricing rule based on the average risk of the participant pool.

The model's central insight is that repo rates are a non-linear function of borrower default risk.

This non-linearity means that averaging borrower-specific OTC prices yields more negative rates than pricing the pooled borrower in CCP markets.

This difference creates a systematic wedge between OTC and CCP rates, where the average OTC rate is typically more negative than the CCP rate in normal times.

This mechanism highlights how counterparty risk is internalized differently across clearing venues, influencing the equilibrium price of scarce collateral.

The model predicts that the CCP–OTC specialness gap compresses during periods of counterparty uncertainty, such as the March 2020 COVID-19 shock.

This compression is weaker for riskier borrowers, as identity-based OTC pricing remains distinct from pooled CCP pricing.

Conversely, the compression is stronger for high-quality collateral, where the interaction between counterparty and collateral risk becomes more pronounced in CCP markets.

Using confidential transaction-level data from the Eurosystem's Money Market Statistical Reporting (MMSR) dataset, the authors find empirical evidence consistent with these predictions.

Following the COVID-19 uncertainty shock, the CCP–OTC differential compressed sharply, with borrowing costs in CCP markets increasing relative to OTC markets by approximately 6 basis points.

These findings are robust across various specifications.