Oracle has experienced a staggering $300 billion decrease in its market value since announcing a major partnership with OpenAI in September 2025. The company's market capitalization fell from approximately $615 billion on September 10 to around $315 billion by November 18, 2025, fueling discussion of a "'Curse of ChatGPT'". This dramatic decline highlights significant investor concern regarding Oracle's strategy, which involves taking on substantial debt to finance the massive AI data infrastructure required by OpenAI. Analysts note that this effectively makes Oracle's stock a public market proxy for OpenAI's ambitions and risks. The sell-off contrasts with the relative stability of broader market indices like the Nasdaq Composite, underscoring the specific investor unease surrounding Oracle's aggressive, debt-fueled AI gamble.