The sell-off was led by London-listed RELX, which saw its stock price slide nearly 13% to 22.49 pounds in afternoon European trading. The decline positioned the company among the steepest fallers on the STOXX 600 index. Similarly, Wolters Kluwer shares fell 9.9% to trade at 72.26 euros, reflecting a broader market anxiety regarding the defensibility of legacy professional service models in the age of generative AI.

The catalyst for the downturn was a series of updates from Anthropic, the developer of the Claude AI chatbot. The company introduced new capabilities for its Cowork assistant via GitHub, specifically targeting legal professionals. According to the startup, these tools are designed to automate high-value tasks that were previously the exclusive domain of specialized, expensive software suites.

The Scale of the AI Threat

The new Anthropic features aim to streamline several core functions that are central to the revenue models of incumbent publishers:

• Contract review and non-disclosure agreement (NDA) triage.
• Compliance workflows and automated legal briefings.
• The generation of templated responses for routine legal inquiries.

While RELX has aggressively integrated its own proprietary technology through LexisNexis Protege and the Lexis+AI platform, investors remain skeptical of the company's long-term competitive moat. Analysts at ING previously cautioned that RELX’s legal division—its third-largest business unit—is increasingly vulnerable to nimble AI startups. The contagion spread to other data-dependent firms, with education publisher Pearson falling 3.8% and the London Stock Exchange Group dropping nearly 8% as the market re-evaluates the value of proprietary data providers in an AI-driven economy.