Antidote, a London-based legaltech company, has raised a $5 million Seed round led by Lakestar, with participation from Concept Ventures, The LegalTech Fund (TLTF), and a group of industry angels. The financing brings Antidote’s total capital raised to $7 million, following a $2 million pre-seed in 2025, and will be used to accelerate product development and expand in the U.S.
The company targets a persistent pain point for large law firms and their corporate clients: complying with Outside Counsel Guidelines (OCGs), which set detailed billing rules that can vary by client and matter. Antidote argues that the prevailing approach, manual review at the end of the month, is both unpopular and costly, contributing to an estimated 8% to 12% of billable hours being lost annually through write-offs and rejected invoices tied to non-compliance.
Antidote’s platform is designed to sit on top of a firm’s existing timekeeping and practice management systems. It automatically reads time entries, checks them against client OCGs and internal standards, flags potential violations, and suggests compliant rewrites before invoices are sent. The company says it has integrated with major practice management and time-recording systems and is already being used by law firms across the U.S., the U.K., and Australia, positioning the product as a proactive, real-time alternative to downstream billing clean-up.
Founder and CEO Nicholas d’Adhemar said Antidote was built to reduce revenue leakage and eliminate a “generally despised” manual compliance process by shifting enforcement earlier in the workflow, when time is entered rather than when bills are being finalized. Lakestar Venture Partner Navid Meyer said the firm is backing Antidote because it addresses an expensive, entrenched industry problem and pointed to d’Adhemar’s experience as both a lawyer and private equity client, as well as his track record building legaltech products in legal spend management.
Antidote is an AI-driven billing compliance tool that extracts rules from OCGs, validates time entries in real time, flags potential issues, and provides corrected, compliant alternatives intended to reduce write-offs and improve trust between firms and clients.
KEY QUOTES
“Law firm billing compliance is one of the biggest sources of revenue leakage inside firms, not to mention being a generally despised manual task that adds to client friction. We built Antidote to remove billing friction by automating compliance for law firms – removing the manual work and shifting compliance upstream, when the work is done, not when you’re trying to send out the bill.”
Nicholas d’Adhemar, Founder and CEO, Antidote
“Antidote is solving a deeply embedded and very expensive problem in the legal industry, and Nicholas brings rare credibility here. He’s lived the problem as both a lawyer and a private equity client and has already built and scaled legaltech startups into category-defining platforms for legal spend management. We’re backing Antidote because it combines a clear product advantage with a founder who has proven he can execute in this market.”
Navid Meyer, Venture Partner, Lakestar
