ChatGPT and Perplexity get the headlines. The two AI assistants quietly reshaping how UK legal buyers find information are Gemini (integrated into Google Workspace and Search) and Copilot (integrated into Microsoft 365 and Bing). Their distribution is different — they reach buyers via the tools those buyers already use rather than as a standalone destination.
Why distribution matters more than usage stats
The standard analysis of AI search market share counts standalone visits to ChatGPT.com or Perplexity.ai. By that measure, Gemini and Copilot look like minor players. The standard analysis is wrong for legal buyer behaviour.
Gemini reaches users through Gmail, Docs, Sheets, the Workspace sidebar, and the Google app on mobile. For a marketing manager drafting a brief on “law firms for our commercial property work”, Gemini in Workspace is the first port of call, not ChatGPT. For a partner doing legal research on a Tuesday afternoon, Gemini in Google Search is what answers the query, not a separate AI destination.
Copilot reaches users through Word, Outlook, Teams, Excel, Edge browser sidebar, and the Bing app. For corporate buyers (in-house counsel, procurement, finance directors) commissioning legal services, Copilot is woven into their daily working environment. They never “go to an AI assistant” — the AI assistant is already there.
How Gemini and Copilot source UK legal information
Both platforms blend live web search with their underlying model knowledge. Gemini reads live Google results plus its model representation. Copilot reads live Bing results plus its model representation. For UK legal queries, the live web results dominate, because the model knowledge has higher uncertainty about specific firms.
The practical implication: ranking well in Google (for Gemini) and Bing (for Copilot) is still the primary mechanism for being cited. AI optimisation is layered on top of organic SEO; it does not replace it. The firms doing well in Gemini and Copilot are firms doing well organically AND doing the AI-specific work (schema, named authors, content depth).
The Bing factor most UK firms ignore
Bing market share in the UK is small (under 5%). Most UK law firms have therefore ignored it. The mistake is that Bing rankings directly drive Copilot citations. A firm that ranks well in Bing for “commercial property solicitor [city]” will be cited by Copilot for that query, regardless of how small Bing is as a standalone search destination.
Copilot is integrated into Microsoft 365, which dominates UK corporate environments. The B2B legal market — commercial, corporate, employment, in-house referrals — runs on Microsoft tooling. Ignoring Bing for SEO means ignoring the AI assistant your B2B buyers are using.
The fix is small. Submit your sitemap to Bing Webmaster Tools. Verify ownership. Optimise for Bing is preferences (slightly different from Google: Bing weights traditional E-E-A-T signals and exact-match anchor text more heavily). Most of the work translates from Google work directly.
The Workspace and Microsoft 365 ecosystems matter for B2B legal
For B2C legal work, ChatGPT and standalone AI assistants are dominant. For B2B legal work — the partner-level work that drives most firm revenue — Gemini and Copilot are the assistants buyers actually use, because they are embedded in the tools those buyers are already in.
A firm targeting in-house counsel, finance directors, marketing managers buying commercial property advice, employment advice, corporate work: those buyers use Workspace or Microsoft 365 daily. Their AI assistant exposure is via Gemini and Copilot, not ChatGPT.
What this means for your firm
Two practical steps. First, set up Bing Webmaster Tools and submit your sitemap. The work is hours, not weeks, and unlocks Copilot citation potential immediately. Second, audit how your firm appears in Gemini for your B2B priority queries, and in Copilot for the same. If the answer is “not at all”, that is the gap.
B2B firms targeting Workspace/Microsoft 365 buyers should treat Gemini and Copilot visibility as priority work, not afterthought work. The buyers are already using these assistants. The firms that get cited get the enquiries.
If you would like to test Gemini and Copilot citation for your priority queries, the SRA-Compliant AI Visibility Audit covers both. Or book an intro call to talk it through.
