WPP slams Publicis over Epsilon ad quality in client-facing report
In a report shared directly with clients, WPP claims that Epsilon’s SSP, Conversant, underperforms on critical ad metrics and pushes Made-for-Advertising (MFA) and clickbait content.
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WPP has taken a rare public swipe at archrival Publicis Groupe, accusing its Epsilon platform of pushing low-quality ad inventory through its Conversant supply-side platform (SSP). In a client-distributed “intelligence report” backed by WPP Media, the group claims Epsilon’s inventory underperforms on key metrics like viewability and attention, falling below accepted industry standards.
The move marks a sharp escalation in tensions between the two ad giants. Global reports claim that WPP CEO Mark Read has privately warned Publicis clients for months, flagging issues related to “made-for-advertising” placements and murky supply path mechanics, some of which allegedly draw from findings in an unreleased Adalytics report.
The unusually direct confrontation signals a deepening rivalry as both holding companies battle for dominance in the programmatic and data-driven media space.
WPP has gone public with a damning assessment of Publicis-owned Epsilon, accusing the platform of trafficking low-quality programmatic inventory. In a report shared directly with clients, WPP claims that Epsilon’s SSP, Conversant, underperforms on critical ad metrics and pushes Made-for-Advertising (MFA) and clickbait content.
The audit, conducted over two days in May 2025, involved a controlled buy through a global DSP. WPP ensured placements came only from direct publishers on Epsilon’s exchange, excluding resellers, and benchmarked performance using third-party firms including Adelaide and Jounce.
What WPP Found
Ads appeared across 503 domains and apps.
Average viewability was 43%, with some placements dipping as low as 1–2%, far below the ANA’s 64.8% benchmark.
26% of impressions were flagged as MFA by independent auditors.
Attention scores lagged by over 40% versus Adelaide’s Q1 2025 standard.
Over 900 sellers appeared simultaneously as publishers and sellers, raising flags on transparency.
Certain domains were labelled as clickbait or IP-infringing by WPP’s partners.
A pointed slide in the report summed up the findings: “The intelligence report unveiled Publicis-owned supply that was MFA or clickbait at worst, and low-quality, low-attention at best.”
WPP went further, stating: “Epsilon (owned by Publicis) has made the decision to onboard these publishers directly onto their platform and is now commercially incentivised to sell MFA, clickbait, and chronically non-viewable inventory to their clients and the wider market.”
All analysis was conducted by third-party verification firms.
Why It Was Made Public
Though WPP Media frequently runs such supply chain audits, this report was deliberately published. The group cited rising concerns over programmatic inventory being resold through global SSPs, noting that it blocks such supply when detected.
The report also alleges that Publicis is not only monetising MFA inventory within its own SSP but is actively distributing it across the broader ecosystem.
The release comes at a pivotal time. With Mark Read stepping down as WPP CEO this year, the move signals a sharpened focus on programmatic accountability.
