New Meridian updates help you make smarter budget decisions.

Summary

Meridian, Google's open-source Marketing Mix Model (MMM), has been updated to provide clearer ROI insights. New features include non-media variables like pricing and promotions for precise impact measurement, channel-level contribution priors to guide the model with business knowledge, enhanced binomial adstock decay functions to measure long-term effects of upper-funnel media, and marginal ROI (mROI) based priors for strategic budget optimization. With 30 new certified global partners and an active Discord community, marketers can deploy Meridian effectively and translate insights into business growth.

Analyst Note

The latest Meridian updates signal a maturation of open-source MMM, directly addressing two pain points for UA and monetization teams: quantifying upper-funnel effects and incorporating business-specific priors. With privacy restrictions eroding last-touch attribution, MMM’s resurgence is inevitable, but its utility has been limited by rigid assumptions. What’s notable here is the addition of non-media variables (pricing, promotions) and enhanced adstock functions, which allow teams to isolate media’s incremental impact from confounding factors—critical for budget negotiations.

The channel-level priors also reduce the black-box nature of MMM, letting teams inject domain knowledge without sacrificing statistical rigor. This positions Meridian as a viable alternative to proprietary models, especially for cost-conscious organizations. The key implication for UA managers is the ability to justify longer-term brand investments with data-backed decay curves, not just immediate conversions.

Meanwhile, the growing partner ecosystem lowers the barrier to adoption. In a market where every dollar must be defended, these updates make open-source MMM more actionable—but only if teams invest in the data hygiene and domain expertise needed to set meaningful priors.