Cannes Lions 2025: Curiosity, the Riviera and a Giant Billboard Questioning Your DSP

This year’s Cannes Lions may have looked like the usual sun-soaked celebration of creativity — celebrity sightings, beachfront panels, and that one guy still trying to network barefoot at 2 a.m. — but beneath the sparkle, the mood had clearly shifted. Call it the year of curiosity, or maybe the year the ad industry collectively said, “Cool activation — now show me the ROI.”

Here’s what went down on the Croisette, and how Viant made a splash of its own.

The Mood: Sober Intentions in a Sparkling Setting

From MediaLink’s closed-door CMO summits to Michael Johnson sightings on Dentsu Beach, Cannes 2025 served as a reminder that even amidst Riviera-fueled revelry, senior marketers are seeking serious answers. As Digiday reports, execs aren’t just there for the creative sizzle — they’re grappling with volatile platforms, regulatory shifts, and a persistent need to “do more with less.”

Even Sir Martin Sorrell got real, declaring, “Uncertainty rules” — a fitting tagline for both the macroeconomic climate and the poolside debates over creators versus craft.

Viant’s Billboard Moment: “Still Trading on a Desk?”

Cut through the clutter (and the Croisette traffic), and you might’ve caught Viant’s cheeky billboard campaign aimed squarely at rival DSPs — particularly The Trade Desk. Towering over the Palais, the lead billboard asked, “Still trading on a desk?” Its follow-up? “ViantAI. The future of digital advertising.”

Our message was clear: simplicity, performance, and transparency are no longer optional — they’re expected. As CMO Jon Schulz told Adweek, the campaign was “meant to be a little bit cheeky, a little bit disruptive,” reflecting the growing appetite among advertisers for DSPs that actually make their lives easier.

ViantAI delivers just that — a generative AI tool that helps advertisers streamline campaign planning by simply inputting a brand, budget, and goal. As Viant CEO Tim Vanderhook explained, CTV accounts for 45% of Viant’s ad spend, with growth that’s twice the rate of the overall market.

AI: From Hype to Hands-On

If 2023 was about AI hype and 2024 was about cautious experimentation, Cannes 2025 marked the moment AI went fully mainstream. As The Wall Street Journal reports, almost every villa, beach club, and branded yacht was talking practical AI applications — from automation to content generation to campaign measurement.

But the real shift? AI wasn’t just a topic — it was a tool. There were demonstrations to show off new AI products built to help smaller advertisers create assets quickly, while Havas used AI to create 3D movie versions of its guests at the Mondrian. One executive even insisted his AI agents should be called “teammates.”

And yes, there were jokes about being replaced by our “teammates” before next year’s festival — but underneath the humor was a growing industry consensus: AI is here to stay, and it’s already reshaping the way we work.

Measurement Is the New Must-Have

While AI dominated the headlines, measurement dominated the whitepapers. In a post-cookie, post-compliance world, marketers are demanding more than impressions — they want real outcomes. Emarketer’s Cannes coverage captured this perfectly: advertisers are asking not just what ran, but where, why, and what it did.

With 71% of U.S. CEOs prioritizing revenue metrics over vanity metrics, and CTV frequency fatigue on the rise, Cannes became ground zero for deeper conversations about standardization, transparency, and attribution.

That’s exactly where Viant’s differentiated approach — from Household ID™ Technology to log-level CTV reporting — shines. As the industry demands more accountability, we’re already delivering it.

Final Take: Cannes Gets Serious

If there’s one theme that tied Cannes 2025 together, it wasn’t just the rise of AI or the demand for measurement — it was intent. Marketers showed up with purpose. DSPs were under more scrutiny. And flashy creative had to coexist with business results.

For Viant, it was the perfect time to reinforce what we’ve always believed: real results don’t need to be complicated. With ViantAI, transparent measurement, CTV,  and a relentless focus on outcomes, we’re helping advertisers move from complexity to clarity — one billboard at a time.