IT stocks are once again in focus, but for all the red reasons. The sector is once again suffering sharp losses after Anthropic highlighted the potential of its Claude Code tool to modernise legacy systems built on COBOL, triggering fresh concerns across the sector. Infosys slipped over 3% while shares of HCL Technologies, Mphasis and Persistent Systems also dipped more than 2% each, while TCS, Tech Mahindra and Wipro also fell around 2%. The weakness across heavyweights pulled the Nifty IT index reached 30,380.55, down 1,169.95 or 3.71% at 11 am. On the NSE, Infosys was down 47.40 points or 3.57%, to 1,280.10. At the same time, TCS fell to 2,599.60, slashing 76.70 points or 2.87% and HCL Tech trimmed 62.20 points or 4.36% to 1,364.00. Wipro tumbled to 201.24 down 4.65 points or 2.26%. Mphasis and Persistent Systems also traded in red, down over 2% and 5% respectively.Market reaction followed Anthropic’s statement that its Claude Code offering can automate a significant portion of the exploration and analysis involved in COBOL modernisation, ET reported. This segment has been an important business area for IBM, which has long promoted mainframe systems designed for large-scale transaction processing environments where COBOL is extensively used. COBOL, or Common Business-Oriented Language, was developed in the late 1950s and continues to be widely deployed in business data processing applications such as payment processing and retail transaction systems. Anthropic estimates that about 95% of ATM transactions in the US still run on COBOL, underlining the scale of potential AI-led cost disruption. “Hundreds of billions of lines of COBOL run in production every day, powering critical systems in finance, airlines and government. Despite that, the number of people who understand it shrinks every year,” Anthropic said in its latest blog post. Selling pressure in the IT pack had already intensified earlier this month when Anthropic unveiled another AI product aimed at automating a wide range of professional workflows. The development rekindled worries that advances in artificial intelligence could chip away at the profitability and competitive moats of traditional IT services providers.