European Central Bank study links euro area bank buyback announcements to 2.5% abnormal returns with limited price effects from execution

The European Central Bank published a blog post analysing how euro area banks’ share prices and volatility react to share buybacks, finding that announcements are associated with a clear positive market response while the execution of buybacks does not systematically move prices. Using an event-study approach, the analysis estimates that bank shares rise by 2.5% relative to the EURO STOXX Banks Index in the five trading days after a buyback announcement, with stronger effects for banks trading below book value. Between 2020 and 2024, 21 large publicly listed euro area banks in the EURO STOXX Banks Index announced 75 buyback programmes, returning EUR 61.6 billion to shareholders, equivalent on average to 8.35% of Common Equity Tier 1 capital as of the first quarter of 2020 for banks conducting buybacks. The announcement effect is similar whether or not the buyback coincides with quarterly earnings calls (43% of announcements), while implied volatility rises temporarily for stand-alone buyback announcements but declines when buybacks are announced alongside earnings. For execution, transaction-level data for four large banks show no difference in abnormal returns between days with and without buyback trades and no statistically significant relationship between abnormal returns and buyback activity as a share of daily trading volume; execution days are associated with lower implied volatility, in a market context shaped by safeguards under the EU Market Abuse Regulation.