Why is Anthropic's new tool, which crushed Tuesday's software stocks, so powerful?

A routine update in the artificial intelligence sector has caused significant turbulence in the legal software sector.

Last Friday, Anthropic launched a legal plugin for its Claude Cowork AI agent, which on Tuesday triggered a collective plunge in related stocks, with several individual stocks falling more than 15%.

This new tool developed by the Claude AI chatbot can perform multiple document-related tasks, including tracking compliance issues and reviewing legal documents. Although this update did not attract much attention outside the legal field, it sparked a sell-off in software and publishing stocks related to the legal industry on Tuesday.

The stocks that suffered the biggest declines on Tuesday include: Vico Group of the Netherlands down 13%, Lixin Group of the UK down 14%, LegalZoom.com nearly 20% drop, and Thomson Reuters down 15%. These stocks have all declined at least 20% since 2026, with the gradual decline at the beginning of the year accelerating sharply after the release of Anthropic’s legal plugin.

(LegalZoom.com nearly 20% drop)

Analysts believe that although the AI disruption threat has been incorporated into Wall Street’s outlook for 2026, investors remain highly cautious about the impact brought by AI agents.

Claude’s Market Position in the Professional Field

In the highly competitive AI market, Claude has become the preferred tool for many legal and financial professionals conducting analysis.

According to Business Insider, well-known short seller Andrew Left stated last year that he used the tool while researching upcoming lawsuits.

This recognition in the professional field makes the legal-related features launched by Anthropic pose a more direct threat to existing legal software providers.

Among the affected stocks, only LegalZoom specializes in legal industry services, helping clients streamline tasks through guides and independent lawyer services.

UK IT group RELX is involved in the legal field through its legal data and analytics platform LexisNexis. Thomson Reuters’ legal business comes from its legal research platform Westlaw. Vico Group of the Netherlands also has operations in legal information services.

Analysts believe that with continuous advances in AI technology, investor confidence in the legal publishing industry may further decline.

Reports indicate that in 2025, many venture capital firms competed to invest in legal tech startups, demonstrating the capital market’s confidence in these AI-centric companies to further disrupt the traditional legal industry.

Risk Warning and Disclaimer

Market risks are present; investments should be made cautiously. This article does not constitute personal investment advice and does not consider individual users’ specific investment goals, financial situations, or needs. Users should consider whether any opinions, views, or conclusions in this article are suitable for their particular circumstances. Invest at your own risk.