pubX raises $5 million and buys Compliant

pubX has built its business on the publisher side, helping media companies price and sell ad inventory for years. Compliant, founded by former Unilever and P&G executives, has focused on the buyer side, serving global brands and their agencies. The acquisition brings both perspectives into one company, which pubX says allowed it to design infrastructure from scratch for agents to trade directly.

The infrastructure is built on Ad Context Protocol (AdCP), an open standard published in October 2025 by ad-tech companies so that agents from different firms can transact. pubX emphasizes trust as a design principle: its agents are trained by pubX, run governance checks on every purchase, and provide traceable reasoning, while Compliant's quality signals—Data Integrity Index and CTV Quality Index—guide what agents consider. Clients set autonomy levels and approve plans at key stages.

The new funding is earmarked for global expansion, building a demand-side business for brands and agencies, continued development of buyer and seller agents on AdCP, and integrating Compliant's signals across the platform. pubX also has an APAC team in Japan and Australia, and says it already provides ad monetization technology to about 150 websites in Japan. A live agent-to-agent media buy for Reckitt's Mucinex brand is scheduled for Oct 7 at Advertising Week New York, with publishers including Paradium.AI and USA TODAY Co. confirming the campaign on the spot.