Anthropic's latest advancement in artificial intelligence has shaken the legal and tech sectors. The company introduced a new plugin for its Claude Cowork agent, capable of managing administrative tasks such as reviewing legal documents and tracking regulatory compliance. Although the launch last Friday went somewhat unnoticed outside the legal field, it triggered a sharp decline in the stock prices of legal software companies on Tuesday. The market's reaction highlights investors' concerns about the rapid disruption AI is causing in the industry. Wall Street had already anticipated the impact of these intelligent agents by 2026, but Anthropic's update has accelerated uncertainty. Claude Cowork has established itself as one of the preferred tools for legal and finance professionals for analyzing legal information. Notable short seller Andrew Left told Business Insider that he has used Claude for litigation-related research, underscoring the tool's utility in the sector. Among the companies most affected by the stock market drop are LegalZoom, focused exclusively on online legal services; RELX, owner of the LexisNexis platform; and Thomson Reuters, with its well-known Westlaw database. So far in 2026, these companies have recorded declines of at least 20%, with losses accelerating after Anthropic's announcement. Confidence in the legal publishing and software sector could be further eroded if AI advancements continue. It is worth noting that in 2025, numerous venture capital firms invested in legal tech startups, convinced of the transformative potential of artificial intelligence in this field.