Microsoft made Copilot for legal generally available on 15 October 2026, adding more than twenty legal skills to Copilot in Word and to Cowork, its agent for work that runs across several files. If your firm already pays for Microsoft 365 Copilot, the Word half needs no purchase and no installation, because Microsoft’s own admin guidance says the legal plugin in Word is enabled for all commercial Copilot subscribers by default.
That default deserves more of your attention than the feature list. Most firms that bought Copilot approved it as an office assistant for email, meeting notes and first drafts. From this week the same licence reviews contracts against a playbook and proposes redlines in a client’s document, and nobody in the firm had to agree to the change.
What arrived on 15 October
In Word, Copilot can review an agreement against a playbook, draft from approved precedents held in SharePoint and propose edits that Word shows as ordinary tracked changes, which Microsoft says apply only when the user approves them. In Cowork the skills reach across agreements, emails, meetings and files, tracking obligations and deadlines through a set of contracts, comparing terms and building case chronologies. Cowork behaves differently on activation, since each user has to add the legal plugin before it does anything.
The skills grew out of Legal Agent, which Microsoft opened to its early access programme in April. Microsoft reports that more than 1,800 users have made nearly 100,000 edits with it since then and kept roughly seven in ten suggestions. Those are the vendor’s own figures from its own trial, and the three in ten that people threw away are the half worth showing your team.
Partner plugins have begun to roll out, among them iManage, NetDocuments, Harvey, Legora and Docusign, with more promised over time. Neither LexisNexis nor Westlaw appears among the research partners Microsoft named, so a firm that researches English law on those services gains nothing on that side yet.
Why the default matters in a law firm
Microsoft states that Copilot works only with content each user can already open, honours sensitivity labels and does not use prompts or documents to train its underlying models. Read the first of those promises with care. Copilot sees whatever your SharePoint and OneDrive permissions allow, so a fee earner who can open every matter folder in the firm lends that same reach to a tool that now compares agreements in bulk. Where your ethical walls rest on habit rather than on permissions, fix the permissions first.
The duty to check the output has not moved. A tracked change proposed by Copilot carries no more authority than one proposed by a trainee, and the solicitor who accepts it owns it. Your supervision of staff who use AI has to reach a capability that appeared overnight inside software everyone already trusts, which is harder than supervising a tool the firm chose and introduced on purpose.
What to decide this month
Ask whoever runs your Microsoft 365 tenant whether the policy called Legal Skills in M365 Copilot in Word has been set, and whether Legal for Cowork is allowed on the Agent Tools page. Then make the choice a partners’ decision rather than an IT default. The skills can stay on, come off, or run for a small pilot group on non-client documents while you test them against your own precedents.
A firm weighing a specialist legal tool against a general assistant now has a third candidate sitting inside software it already licenses, and it deserves the same test as the other two. Google made the same move inside Gemini Enterprise in August, as set out in when legal AI arrives in your cloud platform, so write the decision into your AI use policy with a date and expect to apply it again.
Microsoft announced the release in Introducing Microsoft Copilot for legal on its Copilot blog on 15 October 2026, and its admin page of the same date sets out the default and the controls. Legal IT Insider reported the launch that day.
If you want an independent view on whether Copilot’s legal skills belong in your firm, and on what to switch off before you find out, talk it through with us.
