Source: Sharecast
Shares of credit-checking firm Experian, Dutch firm Wolters Kluwer - which provides professional information, software solutions and services for accountants, lawyers and other professionals - London Stock Exchange Group and Thomson Reuters were also sharply lower after Anthropic launched the tool on its GitHub page.
On its website, Anthropic described the tool as an AI-powered productivity plugin for in-house legal teams, primarily designed for its agentic desktop application Cowork, although it also works in Claude Code.
The tool is part of 11 plugins designed to automate specific tasks within a company.
According to the GitHub page, the legal productivity plugin can "review contracts, triage NDAs, navigate compliance, assess risk, prep for meetings, and draft templated responses". All of this is configurable to an organisation's "specific playbook and risk tolerances," it said.
At 1230 GMT, shares of information and analytics company Relx were down 11%, education publisher Pearson was off 4%, and Informa - which provides events, digital products and academic research services - was 3.8% lower.
LSEG was off 7.3%, while Wolters Kluwer had tumbled 8.8% in Amsterdam and Thomson Reuters was 8.3% lower in pre-market trade.
As far as LSEG is concerned, Max Harper, analyst at Third Bridge, said the move by Anthropic has raised market concerns that proprietary software, such as Workspace, could be rendered redundant, potentially leading to a loss of pricing power.
"Our experts say AI is an enabler, not a threat," he said. "Proprietary data is difficult to replicate via AI alone. Implementations of MCP (Model Context Protocol) act as a core defense in protecting data and can also serve as a growth enabler.
"Pricing power may shift to data rather than platforms. LSEG is positioning itself as a data provider, allowing third-party AI tools (e.g., Anthropic) to act as the 'answer engine'. Our experts note that many of these data sources aren’t public, enabling monetisation regardless of the interface."