International Business Machines Corp. (IBM) sign on the floor of the New York Stock Exchange (NYSE) on Monday, December 8, 2025 in New York, USA.
Michael Nagle | Bloomberg | Getty Images
international business machine After Anthropic’s Claude announced COBOL capabilities, its stock price plummeted, making it the latest victim of rapidly evolving AI technology.
IBM stock fell 11% in afternoon trading Monday after Anthropic outlined a new use case for its Claude Code product: automating exploration and analysis tasks that drive much of the complexity in COBOL modernization.
COBOL stands for Common Business-Oriented Language and is a decades-old programming language widely used in business data processing, IBM’s core business area. COBOL continues to power transaction-intensive systems such as payment processing systems and retail transaction systems, making it a prime target for cost-effective AI disruption.
Anthropic wrote in a blog post on Monday that an estimated 95% of ATM transactions in the United States, for example, are processed in COBOL.
“Every day, hundreds of billions of lines of COBOL run in production environments, powering critical systems in finance, airlines, and government. Yet, the number of people who understand COBOL is decreasing every year,” Anthropic’s blog post says. “AI is great at streamlining tasks that used to make COBOL modernization too expensive.”
Additionally, Claude Code explained that it helps modernize COBOL codebases by mapping dependencies across thousands of lines of code, documenting workflows, and identifying risks that “would take months for a human analyst to surface.”
“Modernizing legacy code has been stagnant for years because understanding legacy code is more expensive than rewriting it. AI flips that equation,” the blog post says.
IBM is the stock that has fallen the most on concerns about AI, which has spooked investors in recent weeks and is contributing to a volatile “sell first, ask questions later” trading environment. On Friday, a number of cybersecurity companies tumbled after Anthropic announced a new feature called Claude Code Security built into Claude Code. The new feature scans codebases for security vulnerabilities and finds software vulnerabilities that can be reviewed by humans. The sector remained under pressure in Monday trading.
Monday’s plunge brings IBM stock down nearly 22% year-to-date.
