ID5

ID5 (operating at id5.io) is a premier adaptive identity resolution platform and universal identity infrastructure engineered for the digital advertising and programmatic ecosystem. Founded in 2017 by Mathieu Roche and Pierre-Antoine Durgeat and headquartered in London, United Kingdom, ID5 replaces fragmented signal tracking and deprecated third-party cookies with a privacy-first, cookieless addressability framework. Under the hood, ID5 utilizes machine-learning-powered identity synchronization, combining encrypted signals (such as hashed emails, page URLs, and IP addresses) into a standardized universal identifier (the ID5 ID). This enables publishers to maximize programmatic yield, advertisers to achieve precise cross-channel targeting, and adtech platforms to optimize match rates while adhering strictly to global data protection regulations like GDPR and CCPA. Backed by over $27M in total venture funding—including a Series B led by TransUnion, S4S Ventures, Progress Ventures, and 360 Capital—alongside strategic acquisitions like TrueData, ID5 powers cookie-free audience identification and attribution across millions of digital properties globally.