ECB Interventions in Distressed Sovereign Debt Markets: The Case of Greek Bonds

We study central bank interventions in times of severe distress (mid-2010), using a unique bond-level dataset of ECB purchases of Greek sovereign debt. ECB bond buying had a large impact on the price of short and medium maturity bonds, resulting in a remarkable “twist” of the Greek yield curve. However, the effects were limited to those sovereign bonds actually bought. We find little evidence for positive effects on market quality, or spillovers to close substitute bonds, CDS markets, or corporate bonds. Hence, our findings attest to the power of central bank intervention in times of crisis, but also suggest that in highly distressed situations, this power may not extend beyond those assets actually purchased.This paper analyses the determinants and effects of ECB interventions in times of severe distress. We focus on the Greek government bond market in mid-2010 and use a unique new dataset to show, for the first time, what type of bonds the ECB bought. We then explore the short-term effects of ECB purchases at the bond-level. The results show a large impact of the interventions on the targeted instruments. Bonds bought by the ECB see a much steeper drop in yields than those not bought. This is consistent with theories of “local supply effects” in segmented or illiquid bond markets.