Microsoft Shares Fall as Anthropic Takes Aim at Excel

Microsoft shares fell during Tuesday trading as investors weighed a new challenge to its Office business from Anthropic. The Claude developer has introduced its own spreadsheet, shared planning board and data workspace, moving beyond AI assistance inside other companies’ software and closer to the tools employees use to get work done. Investing.com reported that Microsoft was down around 2% as the workplace plans came into view. The share price can move again before the US close, and the timing alone cannot establish that Anthropic’s announcement explains the entire decline.

The news follows Anthropic’s 10 November launch of Claude Whiteboards, Claude Sheets and Claude Data. Sheets can build editable trackers and budgets with tabs, formulas, formatting and drop-downs. Whiteboards turns discussion into a collaborative visual plan. Data, previously known as Claude Dashboards, is now generally available for connected company data. The products are available on paid Claude plans, although Whiteboards and Sheets remain in beta and Enterprise administrators have different default settings.

Microsoft has a large, established business selling productivity software to organisations. Excel is not merely a grid of cells. For many customers it sits inside a wider Microsoft 365 arrangement that includes identity controls, storage, Teams, Outlook, administration and support. A new spreadsheet does not replace that bundle overnight, but it does raise a strategic question: if workers start projects in an AI assistant and keep the resulting sheet there, which company owns the daily workflow?

Anthropic’s pitch is that Claude can stay involved as colleagues edit a board or spreadsheet together. Microsoft is pursuing the same broad shift through Copilot across its own applications. The competition is therefore not simply over whether AI can create a formula. It is over where a team begins a task, where the work remains visible and which platform captures the value of continued collaboration.

There are important limits to the immediate threat. Anthropic itself says Claude Sheets has relatively simple spreadsheet functionality at launch. It points users who need the full capabilities of Excel towards XLSX or CSV export and Claude for Excel. That makes the new product a credible test of a different workflow, not evidence that enterprise customers are abandoning Microsoft licences today.

The companies are not only rivals. Microsoft’s name appears among technology companies in a private placement described in Anthropic’s updated US securities filing. That underlines the unusual structure of the AI market, where cloud providers and software incumbents can finance, distribute and compete with the same model developer.

TechBooky recently examined Anthropic’s broader push into work with Claude Duet. Tuesday’s market reaction shows why the latest launch matters beyond a product demo. Investors are testing whether independent AI platforms can claim a larger share of workplace software spending. The next evidence will be adoption, retention and the depth of real spreadsheet use, not one afternoon’s share-price move.