BiddingStack Joins AAO for Agentic Advertising with ADCP
BiddingStack Team
11 min read
Activate Your Media Sales with the BiddingStack Platform for ADCP
The advertising industry stands at the threshold of its most significant transformation since programmatic bidding emerged over a decade ago. With AI agents now capable of discovering, negotiating, and executing media buys autonomously, a new protocol has emerged to standardize this revolution: the Ad Context Protocol (ADCP).
Transfon's BiddingStack Platform has joined AgenticAdvertising.org as a Founding Member, helping publishers and media owners to capitalize on the emerging wave of agentic AI media buying.
Table of Contents
- What Is ADCP and Why Does It Matter?
- Natural Language: Making Advertising Accessible
- ADCP Benefits for Publishers
- ADCP Benefits for Media Buyers
- How ADCP Seller Agents Work
- What ADCP Is Not About
- BiddingStack Platform for ADCP
- BiddingStack Platform for Publishers
- The Future of Advertising Is Agentic
What Is ADCP and Why Does It Matter?
The Next Evolution After OpenRTB
ADCP (Ad Context Protocol) represents the next major evolution of the adtech ecosystem following OpenRTB. While OpenRTB standardized real-time bidding and enabled programmatic advertising to flourish, ADCP introduces something fundamentally different: agentic advertising.
In agentic advertising, AI agents—rather than humans—handle the discovery, negotiation, and execution of media buying at scale. These agents communicate using natural language, interpret campaign briefs, match buyer intent with publisher inventory, and execute transactions automatically.
As the protocol's documentation describes it, ADCP is "the open standard enabling AI agents to execute advertising tasks across any platform". It serves as the blueprint for how AI agents will transact in digital media, establishing common rules and data formats that enable seamless communication between buyer and seller systems.
What Traditional Programmatic Solved, What It Didn't
Traditional programmatic advertising revolutionized the industry by solving two critical challenges. It created inventory liquidity, giving publishers access to a vast pool of demand partners, while simultaneously enabling buyer scale so advertisers could reach audiences across thousands of sites instantly.
However, programmatic did not solve media buying process scalability. Humans remain the bottleneck throughout the workflow. Media buyers spend countless hours managing complex campaign workflows, while publishers struggle to manage fragmented demand and intricate deal structures. Direct deals still require extensive human-to-human communication and manual setup, limiting how much business any team can realistically handle.
Despite sophisticated automation in ad serving and bidding, the strategic and operational layers of media buying remain labor-intensive and difficult to scale.
The Limitations of OpenRTB and Current Programmatic
OpenRTB and the current programmatic ecosystem excel at standardized inventory types like display banners, video campaigns, and standard IAB ad units. But what about emerging and non-standard media formats?
The current ecosystem makes it challenging for these inventory types to participate. Influencer inventory and creator partnerships, custom sponsorships and branded content, AI chat ads within conversational interfaces, recommendation and AI search placements, and virtual out-of-home (VOOH) advertising all struggle to find a place in traditional programmatic.
These formats don't fit neatly into impression-based auctions. They require context, negotiation, and custom deal structures that real-time bidding wasn't designed to handle.
Cost and Efficiency Challenges
OpenRTB's reliance on real-time microtransactions creates inherent inefficiencies. Every impression triggers an auction, multiplying infrastructure and processing expenses, while the split-second nature of RTB leaves little room for strategic negotiation or optimization depth.
ADCP shifts this model entirely. Instead of auctioning individual impressions, AI agents create larger, pre-optimized, pre-negotiated deals. Buyer and seller agents can negotiate on audience segments, engagement rates, or outcomes—reaching agreements before any impressions are served.
This approach reduces overhead while enabling more sophisticated, value-aligned transactions.
Natural Language Making Advertising Accessible
One of ADCP's most transformative features is its embrace of natural language communication. Media buyers can use human language to define campaign intent and objectives, discover relevant inventory across platforms, negotiate pricing and placement terms, and execute deals end-to-end.
For example, a buyer might simply instruct their AI agent: "Find sports fans with high purchase intent, compare prices across all platforms, and activate the best option". The agent interprets this request, discovers matching inventory through seller agents, generates proposals for review, and once approved, activates the campaign.
AI agents communicate agent-to-agent, improving speed and scale dramatically. What once required days of emails, calls, and manual IO processing can happen in minutes.
This natural language interface opens access to participants who were previously locked out—smaller publishers who lack dedicated sales teams, emerging media owners with non-standard inventory, and new buyer segments including smaller brands and agencies can all participate in the advertising ecosystem more easily.
ADCP Benefits for Publishers
For publishers and media owners, ADCP unlocks significant opportunities:
Better Activation of First-Party Data
Privacy-first, non-standard first-party data is more valuable when AI agents can understand and negotiate based on its unique characteristics. Rather than forcing your data into standardized segments, ADCP lets you describe what makes your audience special.
Custom and Non-Standard Media Products
Publishers can finally create and sell custom media products at scale. Whether you're offering sponsored content integrations, newsletter placements, or AI-powered recommendation slots, ADCP provides a unified protocol to package and monetize these offerings.
Increased Inventory Exposure
Your inventory becomes discoverable by a broader buyer ecosystem. Seller Agents expose your offerings to AI assistants and buyer agents worldwide, dramatically expanding your potential demand base.
Easier Discovery for Buyers
By standardizing how inventory is described and discovered, ADCP removes the friction that keeps buyers from finding your premium offerings. Your Seller Agents can articulate exactly what you offer and match it with buyer intent.
ADCP Benefits for Media Buyers
Brands and agencies gain equally compelling advantages:
Discover and Execute at Scale
Buyers can discover diverse media products and execute purchases at unprecedented scale. AI agents handle the heavy lifting of researching options, comparing prices, and managing the execution details.
Reduced Reliance on Intermediaries
Agentic ad demand enables more direct relationships. Buyer agents can connect directly with publisher seller agents, potentially reducing the intermediary fees that currently consume significant portions of media budgets.
Understanding Non-Standard Inventory
Through a unified protocol, buyers can finally understand and evaluate non-standard inventory types. Whether it's a podcast sponsorship, an in-game placement, or a recommendation widget, ADCP provides the common language needed to compare and transact.
How ADCP Seller Agents Work
At the heart of ADCP's publisher-side implementation are Seller Agents. These AI-powered systems operate using MCP (Model Context Protocol) or A2A (Agent-to-Agent) protocols to expose inventory to the buyer ecosystem.
You can find how it works at the ADCP launch video at ADCP Media Buying Demo.
What This Means in Practice
AI assistants such as Claude, ChatGPT, or Google Gemini can discover your media inventory by querying your Seller Agent, evaluate offerings against campaign requirements, negotiate deal terms including pricing, targeting, and placement, and execute transactions once terms are agreed.
This happens AI agent to AI agent, at machine speed and scale. A buyer's AI assistant might simultaneously query hundreds of Seller Agents, compare offerings, and surface the best options for human review—all in seconds.
Prebid and Open-Source Seller Agents
To ensure broad adoption and prevent fragmentation, Prebid has taken over management of the ADCP open-source Seller Agents project. Prebid, the organization that successfully turned header bidding into an open standard, is bringing the same collaborative approach to publisher-side AI agents. The initiative focuses on standardizing Seller Agent implementations, making adoption easier for adtech platforms and publishers of all sizes, and lowering technical barriers across the ecosystem.
Major players including Magnite and PubMatic are participating in defining how Seller Agents should function, ensuring the standard serves the entire industry.
BiddingStack provides Seller Agent Services
BiddingStack provides Seller Agent infrastructure management, including Seller Agent activation and hosting, ADCP enablement services, and managed infrastructure for individual publishers, media owners, and publisher networks. Rather than building and maintaining your own Seller Agent infrastructure, BiddingStack handles the complexity so you can focus on your content and audience.
What ADCP Is Not About
It's important to understand what ADCP doesn't represent:
ADCP is not just automation. It's not about replacing manual processes with scripts. It's about enabling intelligent agents that can understand context, negotiate strategically, and make decisions.
ADCP does not replace human strategy. Media planning, creative development, and brand positioning remain fundamentally human endeavors. ADCP removes execution friction so humans can focus on what they do best.
ADCP does not eliminate premium deals. High-value relationships and custom partnerships will continue to thrive. ADCP simply provides the infrastructure to discover and execute more of them, more efficiently.
Instead, ADCP removes execution friction from media transactions, standardizes communication between disparate systems, and lets humans focus on strategy while agents handle operations.
BiddingStack Platform for ADCP
BiddingStack Joins ADCP as a Founding Member
We're proud to announce that BiddingStack is an ADCP Founding Member. You can find our official listing on the ADCP member directory: adcontextprotocol.org/members/biddingstack.
This membership reflects our commitment to the future of agentic advertising and our belief that publishers of all sizes should have access to this transformative technology.
ADCP Activation for Medium and Small Publishers
One of our core missions with BiddingStack is democratizing access to advanced advertising technology. For ADCP, this means:
Enabling inventory discoverability for a large-scale buyer ecosystem. Your inventory becomes visible to AI agents worldwide through our Seller Agents hosting infrastructure.
Hosting Seller Agents and Buyer Agents on behalf of publishers, media owners, and publisher networks. You don't need to build or maintain AI infrastructure—BiddingStack handles it.
Lowering the barrier to entry for agentic advertising. Whether you're a solo publisher or a network with thousands of sites, BiddingStack makes ADCP accessible.
BiddingStack Platform for Publishers
About BiddingStack Platform
BiddingStack by Transfon is a next-generation header bidding platform built on open source Prebid. We support web inventory across desktop and mobile browsers, mobile app inventory through SDK integrations, video inventory including instream and outstream formats, and non-standard inventory including emerging AI-powered placements.
Publishers using BiddingStack typically see yield improvements of 50% to 200% compared to similar vendors, thanks to our advanced optimization algorithms and comprehensive demand partner integrations.
Non-Standard Inventory Support
As AI transforms how users consume content, new advertising contexts are emerging. BiddingStack supports monetization in AI chat environments where conversational interfaces present contextual opportunities, recommendation feeds where sponsored content appears alongside organic suggestions, AI search results where relevant advertising enhances the search experience, and "AI Ask" and conversational contexts where users engage with intelligent assistants. These emerging formats represent significant growth opportunities for forward-thinking publishers.
Creating New Media Products
Transfon provides tools that allow publishers to build new inventory opportunities based on their unique content and audience, package custom AI-native media products that leverage first-party data, and monetize emerging contexts with ADCP-compatible workflows. Whether you're experimenting with AI-powered content recommendations or developing entirely new advertising formats, BiddingStack provides the infrastructure to bring these products to market.
Why ADCP + BiddingStack Is a Perfect Match
The combination of ADCP and BiddingStack creates a powerful proposition for publishers. ADCP enables discovery of your inventory by AI agents worldwide, negotiation at machine speed with buyer agents, and scalable buying of non-standard media products. BiddingStack provides the infrastructure to host and operate Seller Agents, programmatic yield optimization across all inventory types, and AI-powered media products including chat, recommendation, and search placements.
Together, we unlock the future of agentic AI media buying and selling. Publishers gain access to emerging demand channels while maintaining the yield optimization they depend on today.
The Future of Advertising Is Agentic
The advertising industry is entering a new era. AI agents are already beginning to handle campaign planning, inventory discovery, and deal execution. The publishers who position themselves now will capture the value as this transformation accelerates.
ADCP provides the standard. BiddingStack provides the platform. Together, we offer a clear path to the future of advertising.
Ready to Get Started?
BiddingStack helps publishers increase revenue through advanced header bidding, unlock new AI-native media products, and list inventory for discovery by AI agents worldwide. Whether you're looking to optimize your current programmatic setup or integrate cutting-edge AI-powered ad formats, our team is ready to help.
Contact us at [email protected] or visit BiddingStack.com to learn more about our platform and ADCP activation services.