Legal IT Insider’s 2025 UK Top 200 is out today (19 November), with a brand new GenAI column that shows this technology has gone from a curiosity to a crowded battleground, at least in terms of the top half of the table and in terms of tools that firms have signed up for. Just over 40% of firms in the table (96 of 221) now have at least one Gen AI tool, and those that do use an average of 1.8 products each – confirming that most firms are multi-homing, not backing a single horse. This is an area that is sometimes pitched as a two-horse race, but our GenAI column shows this is not the case.
Across the column:
- Microsoft CoPilot in its various flavours shows up in around 37 firms – by some distance the single most common Gen AI label, reflecting its position as an ambient AI layer in Microsoft-centric firms rather than a dedicated “legal AI system”
- Legora appears in around 21 firms, cutting across Big Law and the upper-mid tier, usually as a contract review or legal assistant platform
- Harvey is present in 16 firms, mostly larger practices, and typically alongside other tools
- ndMAX / ndMAX Assistant is named in around 10 firms, confirming NetDocuments’ success in turning Gen AI into part of the DMS fabric rather than a bolt-on
- Jylo appears in eight firms, often as part of broader “innovation” stacks
- CoCounsel appears in seven, usually in combination with other platforms
- Only four firms explicitly talk about “ChatGPT” into their tech stack, underlining the extent to which Gen AI is being productised and wrapped rather than simply letting lawyers loose in a browser
- A long tail of more specialised or in-house tools – Leah, Lauri Lawyer, Wexler, Jigsaw and firm-specific chatbots – appears in ones and twos.
Taken together, that paints a picture of a market where Gen AI is no longer experimental at the macro level – it is deployed in a meaningful way in nearly half the firms in the table – but is still messy and overlapping at the micro level. Most firms are running two or more tools in parallel and have not yet resolved which of those will be strategic and which will fade away. For now, Gen AI looks less like a new category of system and more like a pervasive layer sitting inside Office, DMS, KM, contract analysis and case-management tools.
Thus we can say: classic AI is embedded in a modest number of targeted use cases; Gen AI is everywhere, messy and overlapping, and may take several years to settle down into a recognisable pattern, but impossible to ignore.
Note on Gen AI reporting, it is even more difficult to keep up to speed on the adoption of Gen AI tools than other technologies, and we may have missed things.
For example, the table is probably under-counting Lexis+AI because we’ve only put it in where there’s clear, attributable evidence for a specific firm. But it is more complicated than that:
- Lexis’s own data shows much broader use: recent LexisNexis surveys say 61% of UK lawyers are already using Gen AI, and just over half of those use purpose-built legal AI such as Lexis+ AI. Obviously that reveals a potential for it being far more widespread than the eight of firms we’ve currently tagged
- Many firms get Lexis+ AI as an extension of their existing Lexis subscription, and treat it as “part of research” rather than something they issue a standalone press release about
- Marketing language is often fuzzy: lots of material says “developed with input from Firm X” or “Firm Y took part in the commercial preview”, which tells us they used Lexis+ AI but doesn’t always say “we have rolled it out firm-wide.”
Because of that, the Gen AI column today shows only the firms where we’ve seen explicit adoption/selection wording, but there may be many more. Please help us keep an accurate record here by telling us what systems you use. See the methodology notes below for more information.
This was extracted from Neil Cameron’s overall analysis of the UK Top 200 2025 data – for the full summary see HERE.
Methodology notes
The table ranks firms by reference to annual revenue figures and includes significant changes and updates from our last updated table in 2022.
In addition to our own proprietary legacy data, the UK Top 200 is the result of multi-prong research as well as direct engagement with law firms.
If a law firm has announced a future migration to a new platform we have used that information – on the basis that most users of the table are interested in current and future developments as opposed to history. However, if we find out that a planned migration has halted, regressed or changed tack, we will update the information accordingly.
There are some firms for whom we have no historical information, mostly due to the change in the Top 200 list itself. All these firm have been invited to provide us with their technology stack information. However, if none has been provided, the table will be empty or will contain information that we believe to be accurate from the sources previously stated.
We believe that we have a high degree of accuracy in this table, but if we have something wrong, then firms are welcome, indeed enthusiastically encouraged, to get in touch and correct our data. Please contact neil@legaltechnology.com or caroline@legaltechnology.com. We are on ET and GMT respectively.
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