Which 2008 event intensified the global stock-market crash when the investment bank Lehman Brothers filed for bankruptcy?

Lehman Brothers’ bankruptcy intensified the global stock-market crash when the investment bank filed for Chapter 11 on September 15, 2008.

Lehman had accumulated large exposures to U.S. mortgages and related securities. As housing prices fell and mortgage defaults rose, investors questioned the firm’s solvency. Negotiations for a rescue failed, and Lehman entered the largest bankruptcy proceeding in U.S. history at that time.

The filing froze credit markets and sharply damaged confidence in banks worldwide. Equity indexes plunged, while governments and central banks introduced emergency guarantees, capital injections and liquidity programs. Lehman’s collapse is often treated as a key escalation of the 2007–2009 global financial crisis, although the crisis had already begun with mortgage and credit-market stress.