The Globe and Mail reports in its Friday, April 10, edition that U.S. software shares tumbled on Thursday. A Reuters dispatch to The Globe reports that investors have sold off stocks in the sector due to concerns that artificial intelligence tools may threaten the industry. The S&P 500 Software and Services Index is down 25.5 per cent this year, including a 2.6-per-cent drop on Thursday. Interactive Brokers analyst Steve Sosnick says, "We're getting back to being concerned about the prior software-specific concerns stemming from AI and private credit that are coming back to the fore." Earlier this week, Anthropic launched a powerful AI model but held off on releasing it widely over concerns that it could expose hidden cybersecurity vulnerabilities. Only a group of around 40 tech heavyweights, including Microsoft and Google, would have access to Anthropic's "Claude Mythos" model. ClearBridge Investments Michael Clarfeld says: "Whether AI spells the end of the software business is an open question. Given the unprecedented dynamism and speed of AI, we do not pretend to have the answers." Cybersecurity firms Cloudflare, Okta, CrowdStrike and SentinelOne dropped between 4.9 per cent and 6.5 per cent.