By Sophia Su, AVP Platform Partnerships, Yieldmo
SPO appears simple – maximize working media dollars and minimize waste. But generalized consensus masks a deeper truth, what SPO means, how it’s implemented, and what outcomes it drives vary significantly depending on who you ask.
Whether you’re a brand marketer, an agency buyer, a trader, a DSP, an SSP, or a publisher, your role has likely defined your understanding of optimization. That diversity among the industry informs how SPO is operationalized across the supply chain.
A Common Goal, Different Starting Lines
When most people think about SPO, the think of efficiency efficiency. Every party in digital advertising wants to ensure more media dollars are spent reaching actual users and fewer are lost to waste, intermediaries, fees, or inefficiencies. Yet, achieving this goal requires different tools, tactics, and metrics depending on where you sit.
For advertisers and their media teams, SPO begins with strategic decisions. Everything from which partners to include and which inventory sources to include, to how to evaluate cost versus value. Strategies might include reducing the number of hops between buyer and seller, consolidating partners, negotiating better rates with DSPs and SSPs, or creating curated private marketplaces (PMPs) that offer both efficiency and alignment with campaign objectives.
However, identifying a strategy is only the first step. For media traders, execution is where the rubber meets the road. Traders need platforms and tools that support scaled implementation of SPO policies. That means DSPs must expose the right levers, UI-based controls, bid filters, and reporting views to allow traders to optimize based on real-time and historical data.
The DNA of SPO: Bid Request Data
Enabling that optimization relies on what some consider the lifeblood of programmatic advertising, bid request data. The bid request carries critical signals, including the app or site domain, seller ID, device type, geographic data, user identifiers, and the Supply Chain Object (SCHAIN). This object tracks the entire journey of an impression, enabling buyers to understand the number of intermediaries involved, which SSPs are processing the bid, and where fees may accumulate.
The Sellers.json and Ads.txt/App-Ads.txt files maintained by SSPs and publishers are essential in validating supply sources and ensuring the legitimacy of media inventory. When leveraged properly, these standards create a baseline for transparency and trust.
But here’s the issue, not all SPO-relevant data is currently standardized, readily available, or usable.
The Gaps Between Data and Action
Many critical signals remain elusive in practice. For instance, while page URL is technically required in most web bid requests, few platforms allow traders to act at the page level. Other attributes, like diversity ownership status, CTV content metadata, or publisher-defined audiences, are either inconsistently passed, poorly standardized, or not surfaced at all within DSP interfaces.
In these cases, the most effective SPO strategies often require collaboration with supply-side partners who have the data, insight, and control to curate inventory that meets specific campaign requirements. Creating PMPs based on proprietary data sets like content classifications, audience insights, or context relevance can be far more effective than relying on bidstream signals alone.
Optimization Is Human, Too
There’s another element of SPO that rarely gets the spotlight, which is understanding the “why” behind a campaign. Advertisers don’t optimize for the sake of optimization. They optimize to achieve something. It could be better outcomes, more efficient performance, alignment with brand values, audience engagement, or market-specific goals. Each campaign has its own objective.
Yet this intent, this is not encoded in the bidstream. It doesn’t show up in an SCHAIN object. It’s rarely found in a UI toggle.
Instead, it exists in conversations between buyers and sellers, in briefings, in planning documents, and in the strategic back-and-forth that occurs long before a campaign goes live. Truly effective SPO strategies should reflect this understanding. That means building custom solutions, measuring against bespoke KPIs, and designing activation tactics that are rooted in campaign purpose and not just process.
This is where partners who can bridge the technical with the consultative excel. The ability to interpret campaign intent and translate that into optimized supply configurations is a value-add that transcends mechanics.
One Concept, Many Applications
Ultimately, the reason everyone has their own “flavor” of SPO is because SPO is not one-size-fits-all. Brands, might want to cut the number of SSPs on a plan. For a publisher, it could be ensuring that their inventory is reachable via preferred pathways. DSPs, are trying to enhance algorithms to prioritize authorized supply. For an SSP, it might mean helping all sides understand how to work smarter together, balancing scale, efficiency, transparency, and campaign fit.
I believe, success lies not in standardizing how we define SPO, but in recognizing the richness of its interpretations and building tools, relationships, and strategies that respect that diversity.Supply Path Optimization (SPO) is one of the most widely discussed topics in programmatic. The goal of
