The Metallgesellschaft (MG) case in 1993 is a classic example of funding liquidity risk. MG sold long-term forward contracts on oil to clients and hedged its exposure by rolling over short-term futures contracts (a stack-and-roll strategy). When oil prices fell, MG faced massive margin calls on its long futures positions, resulting in severe cash flow mismatches and funding liquidity issues, ultimately leading to huge losses. This illustrates the significant risk of hedging long-term liabilities with short-term, mark-to-market instruments.