Anthropic announced that its AI model Claude can streamline COBOL code, the legacy programming language from the 1960s that still powers approximately 80% of global financial transactions, banks, and government systems. IBM's stock immediately fell over 10%, wiping out around $27 billion in market capitalization as investors recognized the threat to IBM's expensive COBOL maintenance and consulting revenue streams. The market reaction demonstrates how AI is rapidly eroding competitive moats built on the scarcity and obscurity of legacy technical knowledge, potentially replacing high-cost enterprise consulting with affordable AI subscriptions.