Westlaw AI vs. Lexis+ AI: what mid-size firms actually found
Westlaw holds the dominant position, with 63% of responding firms naming it as their primary research platform. That makes it the default seat any alternative, Lexis+ AI included, has to unseat. Firms comparing the two are not really weighing raw capability. They are weighing whether the switching cost, retraining attorneys mid-matter, is worth what a challenger platform saves.
| What mid-size firms report | Share |
|---|---|
| On Westlaw as primary research platform | 63% |
| Running a separate AI research tool alongside the primary platform | 38% |
Westlaw holds the default seat other platforms have to unseat
With 63% of responding firms running it as their primary platform, Westlaw is not one option among several. It is the incumbent every other platform, Lexis+ included, has to dislodge. That default status shapes the real comparison: firms are not weighing Westlaw against Lexis+ AI from a blank slate. They are weighing the cost and disruption of switching against staying put with a tool attorneys already know how to open.
Nearly four in ten firms are running a second AI tool; most are hedging, not solving
38% of firms are running a separate AI tool alongside their primary research platform, not because they found a better answer, but because they are not confident the current one is right. Most chose a newer entrant on a shorter term, buying optionality in a market that has not settled. One firm went the opposite direction: attorneys could not prompt the cheaper tool effectively, so they upgraded to a more expensive option. The differentiator between firms managing this well and firms that are not is contract length: the ones who kept initial terms short can move when the comparison changes. The ones who did not are locked into a choice they made when the technology was months younger.
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