What each tool actually does (and stops doing)
**Harvey AI** is a matter-work copilot built for lawyers who already know what a Form 10-K, an SPA, and a litigation hold look like. It draws on a fine-tuned blend of OpenAI and Anthropic models layered with proprietary legal training, plumbed into iManage and NetDocuments so the AI can actually see the firm's document corpus. You can drop in a 200-page asset purchase agreement and ask for a risk-weighted issues list against the firm's playbook, run multi-jurisdiction research with citations, or kick off a due-diligence workflow that touches dozens of contracts in one pass. Harvey explicitly does not try to be a billing system, a docket manager, or a discovery platform — it is the brain that sits next to those.
**Clio Duo** is the opposite shape: a thin, embedded assistant inside a practice management platform you already pay for. It does not pretend to do M&A diligence. It drafts engagement letters, summarizes matter histories, suggests time entries based on calendar and document activity, generates client update emails, and runs natural-language search across your Clio matters. Per https://clio.com/duo/, Duo is positioned as the AI layer that makes solo-and-small lawyers faster at the administrative drag that eats their day. It does not connect to iManage. It does not run predictive coding. It does not produce a deal-room-quality diligence report. That is fine — that is not what a 6-lawyer plaintiffs firm needs.
**Everlaw** is a different category entirely. It is an e-discovery, investigations, and litigation platform — ingestion, processing, review, analytics, and presentation in one cloud product. The AI inside Everlaw is predictive coding, clustering, concept search, Storybuilder for chronology and witness work, and increasingly generative summarization of documents and depositions. Per https://www.everlaw.com/pricing/, the platform is sold per user per year with a storage component, because the cost driver in discovery is data volume, not seats. You use Everlaw when you have a 2 TB document production to review, not when you want help drafting a demand letter.
The honest takeaway: these three only "compete" in the sense that they all show up on the same shortlist when a firm's leadership says "we need an AI strategy." Once you actually decompose the work — matter substance, firm operations, discovery — they sort cleanly into three lanes. The mistake firms make is buying Harvey for a 12-lawyer firm that mostly does PI and family law (waste), buying Clio Duo for a 400-lawyer M&A practice (insufficient), or trying to do e-discovery in Harvey or Clio (don't).