How Countercyclical Capital Buffers Travel: Internal Capital Markets and Domestic Borrowing

Why It Matters

CCyB tightening does not contain risk within the host country; it migrates risk to the parent’s jurisdiction, undermining the intended macroprudential safety net. Policymakers must account for intra‑group financing when designing cross‑border capital controls.

Key Takeaways

• Host‑country CCyB rise cuts German bank credit to subsidiaries by ~10%
• Parents replace lost bank loans with internal debt, keeping subsidiary funding unchanged
• Parent firms boost domestic borrowing (4% bank, 15% non‑bank) and default risk
• Risk migrates to the parent’s home jurisdiction, creating systemic externality
• Macroprudential design must incorporate intra‑group debt flows and cross‑border coordination

Pulse Analysis

Countercyclical capital buffers are a cornerstone of post‑crisis macroprudential policy, intended to curb credit booms by raising banks’ capital requirements. Recent research, however, highlights that the effectiveness of CCyBs can be eroded by spillover channels that bypass the regulated banking sector. While prior studies focused on cross‑border bank arbitrage and bank‑to‑non‑bank substitution, Imbierowicz et al. uncover a firm‑driven leakage: multinational corporations use their internal capital markets to reallocate funding, effectively neutralising the buffer at the subsidiary level.

The authors exploit a natural experiment where German multinationals face foreign CCyB activations while Germany itself remains unchanged. Their granular data reveal that a one‑percentage‑point CCyB increase cuts German bank lending to the foreign affiliate by roughly 10%, yet the subsidiary’s total liabilities, leverage, and default probability stay flat because the parent steps in with internal debt. Financing this internal support forces the parent to tap domestic markets, raising bank borrowing by 4% and non‑bank borrowing by 15%, which lifts the parent’s default risk by about ten basis points. In aggregate, the group’s exposure to German lenders actually grows, illustrating a clear risk migration from the host to the home economy.

These findings have profound policy implications. National macroprudential tools that target only bank‑firm exposures can be circumvented when multinational groups possess deep internal capital markets. Regulators therefore need cross‑border coordination, consolidated exposure monitoring, and perhaps macroprudential instruments that capture intra‑group debt flows. Without such measures, the safety buffer intended to stabilize credit cycles may simply travel across borders, shifting systemic risk rather than reducing it.