pubX raises USD $5m, acquires media quality firm Compliant

pubX raised USD $5 million in a Series A round led by Chicago Ventures and acquired media-quality firm Compliant. The deal combines pubX's ad-trading infrastructure with Compliant's governance and media-quality signals.

The funding will support pubX's expansion in the United States, growth of its demand-side business for brands and agencies, further development of its buyer and seller agents built on the Ad Context Protocol, and integration of Compliant's signals across its platform. Terms of the acquisition were not disclosed.

Based in New York and London, pubX develops infrastructure for agent-to-agent advertising transactions. It began on the publisher side of the market, building tools to help publishers price and sell inventory. Compliant has operated mainly on the demand side, working with brands and agencies on media quality and governance.

Compliant will keep its name and operate as a pubX company. Jamie Barnard, Chief Executive Officer of Compliant, will also become President, Global Demand Growth at pubX, leading growth strategy across agencies, advertisers, and the wider buy side.

pubX has also been expanding geographically. It launched across the wider Asia-Pacific region this year under Takami Kowalski and appointed Andrew Gilbert to lead its Australian operations in September.

Andrew Mole, Chief Executive Officer and Co-Founder of pubX, set out the company's view of how advertising automation is evolving.

"Programmatic took this industry from fax machines and spreadsheets into more automated and real-time platforms in two short decades, and everything we've done since builds on that premise. Agents let us finish what was started. You tell them how you buy, you sign off where it matters, and every page of the brief gets read every single time. For the first time, the infrastructure has caught up with what brands want to achieve with their advertising and how publishers want to sell," said Andrew Mole, Chief Executive Officer and Co-Founder of pubX.

The acquisition brings together businesses that approached the advertising market from opposite sides. pubX's technology is used to build agents that plan, buy, sell, and optimise advertising, while Compliant is known for its Data Integrity and CTV Quality Indexes.

According to pubX, Compliant's signals will inform buyer agents' decision-making before media is purchased. Its system includes governance checks on each buy and allows clients to set the level of autonomy and approve plans at key stages.

Jamie Barnard said the rationale for the acquisition was to bring those signals directly into automated buying decisions.

"For years, brands have searched for high-quality, high-performing inventory with real, relevant and engaged audiences. Compliant built the Data Integrity and CTV Quality Indexes so that they could do that with certainty rather than speculation," said Barnard. "Inside pubX, those media quality and governance signals sit in the decision itself, so an agent weighs them before it buys. This is what gives each CMO the confidence to trust pubX's agents."

Investor backing

Chicago Ventures led the Series A round. The investor pointed to pubX's existing publisher relationships and its focus on infrastructure designed from the outset for software agents acting on both sides of an advertising transaction.

"Every part of the advertising industry is asking how agents will improve buying and selling, and most answers so far are an agentic layer built on existing infrastructure. Co-founders Andrew Mole and Alex Rosen, pubX's CTO, have built advertising infrastructure before, and this time they built it for agents from the start, on both sides of the transaction, with a publisher base that already trusts them and a design that keeps the client in control. That is a rare starting position, and the Compliant acquisition makes it stronger," said Stuart Larkins, Co-Founder and General Partner of Chicago Ventures.

Publisher interest

Several major publisher and agency groups are already using pubX's technology to transact media buys globally. The company argues that one effect of agentic buying is to make publisher inventory more visible to automated buying systems, particularly when publishers can present audience and contextual data clearly.

Stephanie Mazzamaro, Head of Revenue and Data at Paradium.AI, formerly The Arena Group, said that process could help publishers reach budgets that had previously been inaccessible.

"For a publisher, agentic buying is about discoverability. Buyer agents see the audiences and environments we actually have, backed by our first-party data, and that puts us in front of spend that never reached us before, in an environment we can win. It amplifies what our sales team already does well," said Mazzamaro.

Jason Taylor, Chief Revenue Officer at USA TODAY Co, also pointed to visibility and transparency as key issues for publishers as automated buying systems become more common.

"As advertising increasingly moves toward agentic buying, discoverability becomes critical. Publishers that invest in trusted content, engaged audiences, and brand-safe environments should be more visible to AI-powered buying platforms. The opportunity is to create a more transparent marketplace where quality is recognized and rewarded.," said Taylor.