How Did $30B Get Wiped Off IBM In A Single Day?

It is an established fact that IBM is one of the leading tech companies across the globe and the kind of workforce, the employee is magnanimous. However, this leading IT company faced a significant challenge and shockingly, $30 billion, got wiped away from its valuation in a single day.

In a dramatic market reaction, shares of IBM plunged 13 percent in a single trading session, wiping out nearly 30 billion dollars in market value. The sharp fall marked the company’s worst single day decline since October 2000 and stunned investors who had viewed IBM as a stable legacy technology giant.

The trigger was not an earnings miss or a failed product launch. Instead, the selloff followed a blog post published by Anthropic, the artificial intelligence firm behind Claude.

In the post, Anthropic claimed that its AI system can read and analyze COBOL code, the decades old programming language that still powers a vast portion of banking, airline, and government infrastructure in the United States.

COBOL remains deeply embedded in critical systems, including those handling the majority of ATM transactions. For years, IBM’s dominance in this space was reinforced by the scarcity of engineers capable of understanding and modernizing such legacy code. Many original developers have long since retired, making maintenance both costly and complex.

Anthropic stated that its AI tool can map dependencies, document workflows, and identify risks across thousands of lines of COBOL, potentially accelerating modernization timelines from years to months. Investors appeared to interpret this as a direct challenge to IBM’s long standing consulting advantage, triggering the historic market selloff.