Anthropic says Claude Code can speed COBOL modernization; IBM shares fall about 13%

Anthropic published a post arguing that Claude Code can automate the costly analysis phase of COBOL modernization, such as mapping dependencies and documenting legacy workflows. Investors read it as a threat to IBM's mainframe-linked maintenance and migration work, and IBM shares closed down about 13% at $223.35, their steepest one-day fall since October 2000.

• Anthropic post dated February 23, 2026
• Claude Code aimed at mapping, documenting and risk-checking legacy COBOL code
• IBM shares fell about 13% to $223.35 on the day
• Steepest one-day IBM decline since October 18, 2000, per CNBC coverage
• Market concern: AI could shorten or shrink mainframe-linked services work