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The infrastructure layer of B2B programmatic is being redrawn. This week we saw Publicis become the third holding-co to slam The Trade Desk, movements across M&A, and convergence between data players, moats and walled gardens.
FreeWheel shipped agent infrastructure for CTV and declared itself a neutral rail for AI buyers and sellers. Smartly signed a letter of intent to acquire INCRMNTAL and moved measurement inside the execution layer. LinkedIn expanded its creator and CTV moat and quietly became a harder wall to climb over. Viant posted record earnings by leaning fully into autonomous AI campaign execution. The Trade Desk, meanwhile, is facing pressure from every direction — fee compression, agentic disintermediation, and a CEO who’s simultaneously right about AI and wrong about how fast the floor drops. This week Publicis publicaly told their clients to avoid TTD.
Five moves. One direction.
The platforms that control signal, execution, and measurement in a single loop - rather than as three separate vendor relationships - are separating from the rest of the market.
This is what that looks like in real time.
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THE PATTERN - PROGRAMMATIC IS CHANGING RAPIDLY
For a decade, B2B programmatic ran on a three-layer stack. You bought data from one vendor. You activated through a DSP. You measured with a separate tool, usually quarterly, usually after the damage was done.
That model is being compressed into a single continuous loop - and AI agents are the mechanism doing the compressing. All of the major traditional layers of programmatic, most notably the Demand Side Platform, are under immense pressure. Having worked in adtech since 2011, I find this unprecedented. The darling of independent adtech, once on a one way upward journey, is getting systematically attacked across the agency landscape
What’s accelerating this: the emergence of MCP (Model Context Protocol) as a shared language between AI systems and advertising infrastructure. Every major platform move this week — FreeWheel, Viant, even LinkedIn’s CAPI integration — is a play for position inside that loop.
The question for every B2B marketing team isn’t whether this happens.
It’s whether you’re building toward owning signal inside the loop, or renting access to someone else’s.
🔴 THIS WEEKS MAJOR STORY BREAKDOWN
The Trade Desk: Three Holdcos in One Month — The Trade Desk Isn’t Losing an Audit. It’s Losing a War.
What happened:
In an email sent to select clients and obtained by Adweek, Publicis explained that The Trade Desk had failed a third-party audit conducted by FirmDecisions — a specialist media contract compliance auditor — that evaluated the platform’s fee structures and media and data spend. Adweek The audit found that TTD improperly applied its DSP fee to other fees it charged Publicis and some of its clients, billed clients for tools they were automatically opted into without evidence of authorisation, and did not provide the auditor with information necessary to validate that media and data costs were invoiced at cost and without mark-up. Adweek This follows Dentsu and WPP, who quietly stepped back from TTD’s OpenPath supply initiative weeks earlier over what they described as hidden fees, transparency concerns, and lack of clarity on where ads ran. Campaign Live Three of the Big Five holdcos. One month. All citing transparency.
The Trade Desk stock has retreated 33% in 2026. Campaign Live The CEO responded by personally buying $148 million of shares. The board lost a member. Rosenblatt and Stifel both downgraded the stock.
The official version — and why it’s only half the story:
Take the audit findings at face value for a moment. Fee complexity, auto-enrollment in tools, audit access refused. That’s a real problem and TTD’s own fee structure, transparent in principle, confusing in practice, has made it harder on itself. It has been slow — and I’d argue stubborn even — in response to legitimate concerns about the Kokai interface. Personally I never liked the withdrawal away from a programmatic traders interface and the force manoeuvre of putting new features into Kokai only. Worst then that, clients face more bureaucracy than they should when trying to access their own data. Adweek Those are genuine operational failures. Worth fixing. Worth holding TTD accountable for.
But they don’t explain the pattern.
Three holdcos. Same month. Same language. Same framing.
That’s not three separate audits arriving at the same conclusion independently.
That’s a coordinated moment.
My read: this is a territory war, not a billing dispute
Here’s the structural reality that nobody is saying loudly enough.
The Trade Desk spent years building the buy-side’s most powerful independent platform — and then made a strategic decision to move into the supply chain. This is becoming table stakes, and the programmatic ecosystem of Supply Side Platforms representing publishers (SSP’s), and Demand Side Platforms (DSP’s) representing media buyers is dead. This was a significant line of discussion that I had with adtech titans in New York during the first week of March. Both sides have converged into a singular access layer, and their competition is now less themselves, as truley alterntive ways of buying media, driven by AI protocols.
Thus, OpenPath wasn’t just a transparency initiative. It was designed to make ads perform better and help buyers directly purchase publishers’ inventory — a viable alternative to Google’s infrastructure. Adweek That sounds great for advertisers. And maybe it is.
But here’s what OpenPath actually does to the holdco trading desk model: it removes the agency’s supply-path optimisation layer from the equation. SPO is one of the services agency trading desks charge for — and earn margin on. OpenPath, positioned as “at cost,” directly threatens that revenue line. Agencies have spent years accepting lower takes and making their margin opaquely out of media deals, and curation has opened up a route to making margin from the supply layers. This very much links to our discussions about Principal Media, and the billion dollar agency revenue game that comes with it
Industry observers pointed to potential overlap between OpenPath and services traditionally handled by agency trading desks, including supply-path optimisation and inventory curation. e4m When WPP cited “overlap with agency services” as a concern about OpenPath, they weren’t confused about what OpenPath does.
They were telling TTD to get out of their lane.
The Publicis audit, real as its findings may be, arrived at exactly the right commercial moment to give the holdcos a legitimising narrative for what is fundamentally a power move. You can’t tell your clients “we’re stepping back from TTD because it competes with our trading desk margin.” But you absolutely can tell them “we failed an independent audit and we have a responsibility to protect your media spend.”
Same outcome. Much cleaner story.
The irony that the industry isn’t saying:
The loudest voices calling out TTD on transparency are the same organisations currently facing their own transparency crisis.
The world’s largest agencies essentially pitch for free and operate on razor-thin disclosed margins. To survive, they have to generate profit from hidden fees and undisclosed arrangements. Adweek WPP is currently facing a $100 million whistleblower lawsuit alleging nearly $1 billion annually in undisclosed principal trading income — with 97.4% of GroupM’s proprietary inventory allegedly unused by its own largest clients. The same week they exited OpenPath over “transparency concerns.”
That is not a small irony.
It’s the defining contradiction of the current holdco moment.
What TTD’s actual problem is:
Strip out the agency politics and TTD still has a real structural challenge — one that exists regardless of who’s auditing them.
Unlike Google, Amazon, and Meta, which benefit from inventory ownership and closed-loop measurement systems, The Trade Desk sits entirely on the buy side. That independence is the product. But that same structure means TTD has no captive inventory to fall back on if clients walk. 24/7 Wall St. Publicis accounts for more than 10% of TTD’s gross billings. Two ad holding companies would each account for over 10% of 2025 gross billings — combined, 30%. Investing.com A DSP built entirely on the buy side, with no inventory ownership, dependent on holdco relationships for 30% of gross billings, now facing fee pressure from agentic systems that automate what human traders used to do manually — that’s a structural pressure stack, not a billing dispute.
Jeff Green’s $148 million personal share purchase says he believes the platform wins long-term. He’s probably right about the thesis. The question is whether he’s right about the timeline.
The supply-side signal worth tracking - where is all this ad spend going?
The deeper shift underneath this story — and one that barely got coverage — is where the smart money is actually moving.
As TTD gets squeezed from the buy side, the supply side is having a very different week. Curation platforms, deal marketplaces, and SSP-layer infrastructure are gaining traction precisely because they offer what OpenPath promised but without the conflict of interest: transparent supply paths, brand-safe inventory packaging, and signal-rich deal IDs that don’t require the buyer to route through a DSP’s proprietary pipe. They also offer post auction discounts, which equate to revenue lines for agencies
The agencies exiting OpenPath aren’t abandoning supply-path thinking. They’re building their own. Publicis has Epsilon. WPP has its own data infrastructure. They want the supply advantage TTD was building — they just want to own it themselves.
This is the curation layer becoming contested territory. And it confirms something we’ve believed at FunnelFuel for a while: the value in B2B programmatic isn’t at the DSP execution layer. It’s in proprietary signal, curated supply, and the intelligence layer that sits between audience data and inventory — the part that’s genuinely hard to replicate and impossible to audit away.
Your takeaway:
Stop reading this as a story about TTD’s billing practices.
Read it as a story about who controls the supply chain in a post-OpenRTB world — and why every major player is willing to pick a very public fight to answer that question.
The holdcos want the supply advantage back. TTD wants to disintermediate the holdcos. Neither side is being fully honest about why.
The B2B buyers in the middle should be asking a different question entirely: if my DSP and my agency are fighting over who controls the path to inventory, what does that mean for the quality, transparency, and cost of the media I’m actually buying?
The answer is: more than you think. Not for the first time, it is why you need expertise on your side. Simply reply to this email, it goes straight to my inbox, and we will bring you up to speed on what we’re doing at FunnelFuel to aid B2B buyers in navigating this complex world
Sources: Adweek — Publicis leaked memo and FirmDecisions audit reporting,
17 March 2026 AdAge — Publicis no longer recommends TTD,
17 March 2026 Adweek — Dentsu and WPP OpenPath exit,
February 2026 Campaign US — TTD/holdco fallout TL;DR,
March 2026 Adweek — The Trade Desk-Publicis Fight Is Really a War Against Transparency,
March 2026 24/7 Wall St. — TTD two-day selloff and CEO share purchase reporting
Investing.com — Rosenblatt and Stifel downgrades
STORY 2: FreeWheel ships an MCP server — the agent infrastructure race is live
What happened: FreeWheel launched AI agent infrastructure for CTV this week — an MCP server that lets agency AI systems plug directly into FreeWheel’s platform, with built-in intelligence tools that monitor deal performance and trigger optimisation without human input. PMG signed on for the pilot.
Why it matters: This is the first time a major sell-side platform has shipped agent infrastructure as a product, not a prototype. At CES, NBCU, FreeWheel, and Newton ran a live experiment showing AI agents planning and optimising a campaign by communicating directly over MCP. This week, that architecture became commercially available.
The infrastructure question underneath this: who becomes the connective tissue between AI agents and inventory? FreeWheel is betting the answer is “neutral SSP-layer infrastructure.” The platform that controls that endpoint controls the pricing relationship — not the agency, not the brand.
This captured my attention because it points to the post programmatic competition that I outlined above as the real competitors against the likes of The Trade Desk.
My view: There’s a standards war running in parallel. AdCP ((backed by Scope3 and Brian O’Kelly - BOK is an adtech godfather and Scope3 has real credibility within adtech circles as a result), PubMatic, Yahoo, Triton, and others)) is building an agent-native protocol from the ground up — the OpenRTB of the agentic era. ARTF is a rival framework. Messy coexistence for 18–24 months is the likely outcome, then convergence. Don’t pick a side yet. Do ask your agency what their MCP integration strategy is — because within two years, their AI agent will be making deal decisions on your budget without asking.
STORY 3: Smartly acquires INCRMNTAL — measurement is being absorbed into execution
What happened: Smartly signed a letter of intent to acquire INCRMNTAL, a Tel Aviv-founded incrementality measurement startup that measures causal lift without user-level tracking and without pausing campaigns. The deal closes within weeks.
Why it matters: INCRMNTAL does something the industry has talked about for years but rarely operationalised: always-on, causal measurement that doesn’t require a controlled experiment. No holdouts. No paused campaigns. No quarterly retrospective. It analyses natural variation in campaign activity to calculate true incremental impact across every channel — CTV, DOOH, audio, social, display.
Smartly’s existing platform processes hundreds of billions of creative assets annually. Pulling real-time measurement inside that execution engine means the feedback loop between “what ran” and “what worked” shrinks from weeks to hours.
My view: This is bigger than one acquisition. It’s a signal that measurement is leaving the strategy deck and entering the activation layer permanently. This will be a huge component of agenctic buying. For B2B teams with 60–90 day sales cycles and attribution models that barely hold together, this points to where the industry is heading: incrementality as a live signal inside campaign execution, not a post-mortem you run once a quarter and file somewhere. Start asking your measurement vendor how they plan to survive when the DSP does this natively.
The last two moves, and what I’d change in a B2B buying plan because of all five, are below.