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(Bloomberg) — Jittery investors scanning the horizon for winning artificial intelligence bets glommed on to Thomson Reuters Corp. after its legal tools earned kudos from AI juggernaut Anthropic PBC.

Shares of the financial services company soared as much as 14%, notching the biggest intraday gain in 26 years, after its AI tool for lawyers, CoCounsel, was touted on stage at an Anthropic-hosted briefing. Thomson Reuters’ Chief Executive Officer Steve Hasker also presented at the event.

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It was a much needed boost for the stock of the Toronto-headquartered firm which has lost more than half its value since hitting an all-time high in July. Disappointing sales growth was at least partly to blame, as were fears of AI encroaching on its business.

The jump comes as the market veers between AI optimism that the technology will turbo charge stock market growth and pessimism that AI will unwind many business models, but most especially those of software services firms.

“We’ll see if today’s early gain holds and gets the shares closer to the level at least seen on Feb. 3,” National Bank Financial’s Adam Shine wrote in a research note. He rates the stock outperform, though his C$175 price target is below the stock’s closing record of C$293.53.

Thomson Reuters also announced CoCounsel hit one million users, which the firm said marked a shift from “experimentation to production.”

The company, in a statement, listed a few AI tools it was working with, including Anthropic’s Claude model, OpenAI Inc.’s GPT and Alphabet Inc.’s Google Gemini platform.

The announcement comes weeks after Anthropic unveiled a legal AI tool plug-in for its agentic Claude Cowork AI platform on Feb. 3, which triggered a market rout for companies in the legal information space and other software firms.

“It will likely take more time and understanding for the market to better assess how the company continues to benefit from AI,” Shine said. AI disruption may not be as bad as “suggested by the rather aggressive valuation re-rating experienced in recent months, let alone in recent weeks.”

Thomson Reuters competes with Bloomberg LP, the parent of Bloomberg News. Shares closed 11% higher at C$123.45 on Tuesday.

(Updates with closing share price in final paragraph.)

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