The new Signal & Noise episode with Mathieu Roche, “Who Replaces Switzerland?”, is now live. Listen (or watch): Who Replaces Switzerland? Mathieu Roche on Rebuilding the Identity Commons

Mathieu Roche is Co-Founder and CEO of ID5. He has spent close to a decade arguing that advertising needs a neutral identity layer that no one owns outright, which makes him a front-row voice on what the Publicis-LiveRamp deal means for the industry now that the dust has settled.

LiveRamp spent years as the neutral rails of data-driven advertising. The headlines about Publicis’s $2.2 billion acquisition have faded, but the question of what replaces those rails is still wide open. Mathieu returns to Signal & Noise, and he, Brett House, and Rio Longacre shed new light on what comes next.

RampID is only one piece of what LiveRamp does, and he estimates up to half of LiveRamp’s business is at risk, since many brands won’t keep their data with a company owned by an agency that also serves their competitors.

Mathieu explains why match rate is the least understood metric in advertising, and how performance TV and agentic media buying make identity even more important.

By Rio Longacre

Brands spent a decade pulling customer data into Snowflake, Databricks, BigQuery, and other cloud platforms, then started sending copies of it back out to every DSP, social network, and clean room that asked.

Rio argues the activation platform rarely needs the customer record. It needs a signal: is this person a customer, are they eligible for the offer, should we bid? Building audience logic where the data already lives means fewer copies, simpler governance, and the current context AI agents will need to make decisions.