
Antidote, an AI-powered billing compliance platform for global law firms, has raised $5M in a seed funding round to accelerate product development and international expansion.
The round was led by Lakestar, with participation from Concept Ventures, The LegalTech Fund, and a group of industry angel investors. The funding follows a $2M pre-seed round completed in 2025, bringing Antidote’s total funding to $7M.
Addressing revenue leakage in legal billing
Law firms increasingly face complex Outside Counsel Guidelines that govern how work must be billed. Despite this, many firms still rely on manual, end-of-month billing reviews, a process that often leads to rejected invoices, write-offs, and strained client relationships.
Industry estimates suggest that 8–12% of billable hours are lost each year due to non-compliance with client billing rules, creating significant revenue leakage across large firms.
Shifting compliance upstream with real-time checks
Antidote is designed to move billing compliance earlier in the workflow. The platform integrates directly with existing time-recording and practice management systems, reviewing time entries in real time rather than after invoices are prepared.
Each entry is checked against client-specific OCGs and internal firm standards, with the system flagging potential issues and suggesting compliant revisions before billing takes place.
Adoption across major legal markets
Founded to eliminate friction caused by manual compliance processes, Antidote is already used by law firms in the US, UK, and Australia. The company positions its software as a way to reduce administrative burden while improving revenue realisation and client satisfaction.
The platform’s proactive approach aims to minimise rejected bills and reduce the need for late-stage corrections.
Product expansion and US growth
The new funding will support the next phase of Antidote’s growth, with a focus on advancing its AI-driven compliance capabilities and expanding its presence in the US market. The company plans to deepen integrations with legal practice management and timekeeping systems while scaling adoption among firms seeking automated, real-time billing compliance.
Antidote says its goal is to help law firms reduce write-offs, unlock revenue, and modernise billing operations without disrupting existing workflows.