According to Anthropic's release notes, Claude is now generally available as a Microsoft 365 add-in for Word, Excel, and PowerPoint, with an Outlook add-in entering public beta for paid plan subscribers. The integration maintains conversation context across Office applications and can sync edits between open files simultaneously. In Outlook, the add-in offers inbox triage and draft reply features. The rollout extends Claude's reach into the productivity software used by hundreds of millions of office workers worldwide, putting it in direct competition with Microsoft's own Copilot features built into the same applications. Unlike Copilot, which is tightly integrated into Microsoft's infrastructure, Claude's add-in approach allows Anthropic to reach enterprise users through the Office ecosystem without a formal platform partnership.