Antidote is a London-based legaltech company, co-founded by CEO Nicholas d'Adhemar, that automates billing compliance for enterprise law firms against clients' Outside Counsel Guidelines (OCGs). It raised a $2 million pre-seed round in 2025 and a $5 million seed round in January 2026 led by Lakestar, with participation from Concept Ventures and The LegalTech Fund, bringing total funding to roughly $7 million as the company expands into the U.S. market.

Antidote is a London-based startup automating law firm billing compliance against Outside Counsel Guidelines.

Antidote Legal Ltd - AI billing compliance company profile

Antidote Legal Ltd

Very Early-Stage: Founded in 2025 with its first meaningful institutional round closing only in January 2026, so long-term reliability and ROI data are still limited.

No Independent Review Data: Not yet present on G2, Capterra, or similar platforms, making it hard to verify real-world performance from independent users.

Narrow Use Case: Solves billing compliance specifically and offers nothing for legal research, drafting, or contract analysis, so it is an add-on to a firm's stack rather than a broad AI platform.

No Published Pricing: Firms must contact sales to get a quote, making early cost comparison against alternatives difficult.

Solves a Quantified Problem: Directly targets the 8-12% of billable hours industry estimates say are lost annually to Outside Counsel Guideline write-offs and rejected invoices.

Upstream Compliance: Flags likely OCG violations as time entries are recorded, rather than after an invoice is drafted and rejected by the client.

Integrates With Existing Systems: Works with a firm's existing time-recording and practice-management software rather than requiring a full workflow replacement.

Credible Early Backing: Raised $7 million total, including a $5 million seed round led by Lakestar in January 2026, with participation from The LegalTech Fund.

<h3><strong style="background-color: transparent; color: rgb(0, 0, 0);">Introduction</strong></h3><p class="ql-align-justify"><span style="background-color: transparent; color: rgb(0, 0, 0);">Antidote is a London-based legaltech startup, co-founded by CEO Nicholas d'Adhemar, that automates billing compliance for enterprise law firms. Rather than being a general legal research or drafting tool, Antidote focuses narrowly on one costly, unglamorous problem: making sure a firm's invoices actually comply with each client's Outside Counsel Guidelines (OCGs) before they go out, instead of after a client rejects them. The company raised a $2 million pre-seed round in 2025 and a $5 million seed round in January 2026 led by Lakestar, bringing total funding to roughly $7 million as it expands from the UK into the US market.</span></p><h3><strong style="background-color: transparent; color: rgb(0, 0, 0);">How It Works</strong></h3><p class="ql-align-justify"><span style="background-color: transparent; color: rgb(0, 0, 0);">Antidote ingests each client's Outside Counsel Guidelines, a firm's own billing policies, and historical billing data to build "Individual Client Standards" defining what each client will and will not approve. It then continuously analyzes time entries as they are recorded, flags likely OCG violations or non-compliant language before an invoice is sent, and suggests corrected entries that a partner or fee earner can accept, edit, or dismiss. The company cites industry estimates that 8&ndash;12% of billable hours are lost annually to OCG-related write-offs and rejected invoices, which is the core inefficiency Antidote is built to reduce.</span></p><h3><strong style="background-color: transparent; color: rgb(0, 0, 0);">Pricing</strong></h3><p class="ql-align-justify"><span style="background-color: transparent; color: rgb(0, 0, 0);">Antidote does not publish public pricing. As a compliance tool sold to enterprise and large law firms and integrated with existing time-recording and practice-management systems, pricing is quote-based and likely scales with firm size and billing volume; interested firms should contact the company directly.</span></p><h3><strong style="background-color: transparent; color: rgb(0, 0, 0);">User Reviews and Ratings</strong></h3><p class="ql-align-justify"><span style="background-color: transparent; color: rgb(0, 0, 0);">As a seed-stage company that only raised its first institutional funding round in January 2026, Antidote does not yet have a meaningful footprint on independent review platforms such as G2 or Capterra. Its public validation to date rests on its funding (Lakestar, Concept Ventures, The LegalTech Fund) and its stated value proposition around reducing OCG write-offs, rather than aggregated third-party user reviews.</span></p><h3><strong style="background-color: transparent; color: rgb(0, 0, 0);">Verdict</strong></h3><p class="ql-align-justify"><span style="background-color: transparent; color: rgb(0, 0, 0);">Antidote addresses a real and quantifiable pain point &mdash; OCG non-compliance write-offs &mdash; with a focused product rather than trying to be a general-purpose legal AI tool, which is a sensible strategy for a young company. It is worth watching for firms with significant OCG friction and enterprise billing systems already in place, but as a 2025-founded, seed-stage company it lacks the long operating history and independent review volume of more established legal ops vendors, so early adopters should treat it as a promising but unproven bet.</span></p>

Independent 2026 review of Antidote, the London-based AI platform automating law firm billing compliance against Outside Counsel Guidelines.