Non-Endemic Retail Media: The Relevance Problem Behind the Next Growth Opportunity

Retail Media was built around a direct commercial relationship. A brand sells products through a retailer, advertises within that retailer’s ecosystem and measures the resulting sales. By connecting media exposure with transactions, retailers gave brands something traditional digital advertising often struggled to offer.

Now Retail Media Networks are looking beyond the brands already on their shelves. Non-endemic retail media brings insurers, automotive companies, travel providers and subscription services into environments where their products are not sold. These advertisers may value a retailer’s audience, locations and first-party data, bringing new budgets into the channel.

But their arrival changes the proposition. If the advertised product cannot be purchased from the retailer, why does its message belong in the shopping experience? And if the eventual purchase happens elsewhere, what can the retailer actually measure?

IAB Europe’s September 2026 guide to endemic, near-endemic and non-endemic advertising provides the definitions and measurement principles for examining these questions. The four-part decision model later in this article is my own proposal for applying them. [1]

Retail Media Was Built Around Products on the Shelf

The first generation of Retail Media worked especially well for endemic advertisers: brands whose products customers could buy from the retailer. A shopper searches for a product, sees a sponsored placement, visits a product page and completes a purchase. The retailer can connect many of these interactions within its own environment.

The model creates a powerful sequence:

Shopper Intent → Media Exposure → Retailer Transaction → Measurement

For advertisers, the connection between investment and sales is relatively clear. For retailers, supplier demand can turn customer relationships, commerce data and digital inventory into a new revenue stream.

The model also established an expectation: a Retail Media Network should be able to explain how its advertising connects to a commercial outcome. That expectation becomes harder to fulfil as networks seek budgets beyond their existing suppliers.

What Counts as Non-Endemic Retail Media?

IAB Europe defines an endemic advertiser as one whose product shoppers can buy from the retailer. A near-endemic advertiser does not sell that product there, but has a credible connection to the retailer’s categories, usage occasions or customers. A non-endemic advertiser primarily uses the retailer’s audience, data or media reach without an on-platform sale. The classification depends on the retailer: the same brand may fall into different categories in different networks. [1]

Consider a consumer electronics retailer. A television brand stocked by the retailer is endemic. A streaming subscription that makes the television more useful could be near-endemic. A car manufacturer seeking to reach the retailer’s audience may be non-endemic.

These labels describe the commercial relationship. They do not automatically tell us whether a specific advertisement is relevant.

An offer from a complementary service can still feel intrusive if it appears at the wrong time. Conversely, a brand outside the retailer’s assortment may have a credible reason to address a well-defined audience in an appropriate environment. Classification should therefore begin the evaluation rather than settle it.

IAB Europe’s guide cites eMarketer research indicating that 58% of advertisers want to use retail data for audience targeting. It also cites a forecast of 29.6% growth in off-site non-endemic Retail Media spend in 2026. These are eMarketer figures reported by IAB Europe; the original studies’ geographic scope and methodology must be checked before treating them as European estimates. [1]

The demand is attractive. The harder question is which parts of it a retailer should accept.

Non-Endemic Retail Media Needs More Than Audience Matching

Retailers possess more than media inventory. They have a relationship with shoppers who arrive with particular needs and expectations. Their data is valuable partly because it reflects real commerce behaviour, not just a broad interest profile.

As Retail Media Networks expand, they may be tempted to treat every audience or placement as an opportunity to sell additional advertising. That approach could generate revenue while weakening the context that makes retail inventory distinctive. It also builds on a tension explored in my article on Retail Media interoperability: the value of retail data grows when it can be used beyond a closed environment, but the retailer still needs to govern how that happens.

IAB Europe argues that retailers should act as gatekeepers for relevance, trust and shopper experience. A partnership needs a credible connection to the audience, location, shopping mission or customer journey. [1]

In practice, relevance should be judged at the level of the moment. A mobile plan promoted next to a smartphone may answer an immediate question. The same message inserted into an unrelated product comparison might simply interrupt the shopper. A campaign using retailer audiences off-site may make sense even when the advertiser would not belong on a product detail page.

Advertiser approval therefore needs to include the proposed placement and the shopper’s likely purpose at that moment.

The IAB guide includes a public MediaMarkt example involving shoppers interested in smart technology for dogs and partnerships with pet-related advertisers. It describes those opportunities as near-endemic: the connection comes from an adjacent customer need, even though the advertised products are not sold by the retailer. The example illustrates the relevance logic; the guide does not publish campaign results that would prove effectiveness. [1]

The Closed Loop No Longer Closes Itself

Relevance determines whether an advertisement makes sense to the shopper. Measurement determines whether the investment makes sense to the advertiser.

With endemic campaigns, the retailer can often observe sales of the advertised product in its own transaction data. For near- and non-endemic campaigns, the desired action may occur on an advertiser’s website, at a dealership or through another provider. Exposure and outcome sit in different systems.

The sequence becomes:

Retailer Audience → Media Exposure → External Action → Shared Measurement

That final connection requires a deliberate mechanism. IAB Europe recommends agreeing on the primary outcome, available data sources, attribution window and any necessary data collaboration before activation. If conversion is the objective, a dedicated landing page, sign-up flow, code or other trackable action may help connect exposure to a later result. [1]

Not every campaign should be judged by immediate sales. An awareness campaign may need verified delivery and brand outcomes; a lead-generation campaign needs evidence of qualified responses. The important point is to match the measurement promise to what the retailer and advertiser can actually observe.

The resulting offer may be valuable, but its evidence must be described with the same precision as its audience.

My Non-Endemic Value System

The IAB guide defines the categories and sets out measurement considerations. It does not prescribe the following operating model. Based on its principles, I propose four connected decisions that a retailer can use before accepting a campaign:

Shopper Context → Placement Fit → Shared Objective → Outcome Evidence

1. Shopper Context

Why might this advertiser matter to this shopper? A complementary product, a related service, a shared use occasion or a relevant location can create a legitimate connection. A broad demographic overlap is a weaker reason on its own.

2. Placement Fit

Does the message belong in the particular format and moment proposed? An advertiser may be relevant in an off-site audience campaign but inappropriate beside an unrelated on-site product search. The placement is part of the proposition, not merely a delivery choice.

3. Shared Objective

Are the retailer and advertiser pursuing awareness, consideration, leads or sales? Different objectives need different creative, commercial expectations and measures of success. They should be agreed before the campaign is sold.

4. Outcome Evidence

Who can observe the outcome, and what evidence can both parties provide? Retailer media reporting, advertiser conversion data, independent research or an agreed data partnership may each play a role. None should be presented as proof of a result it cannot establish.

Together, these decisions turn the IAB principles into a practical approval process. A partnership should progress only when its customer context, format, objective and evidence form a coherent proposition.

The Cost of Opening Too Widely

There is a tension at the centre of non-endemic growth. The easier it becomes for any advertiser to buy retail inventory, the more a Retail Media Network risks resembling a general-purpose media owner. It may gain short-term budget while losing some of the differentiation that attracted advertisers in the first place.

Imagine a retailer filling high-visibility placements with unrelated campaigns because they command attractive prices. Each sale of inventory adds revenue. Yet shoppers may begin to ignore those spaces, and brands that do belong in the shopping journey may find themselves competing with messages that add little to it. The retailer then has to sell reach and impressions rather than the commercial context that originally justified a premium.

There is also an organisational cost. Sales teams have an incentive to accept new categories, while ecommerce, merchandising and customer-experience teams may carry the consequences of poor placements. Without shared criteria, the same campaign could be approved in one market and rejected in another, leaving the network with an inconsistent proposition for both advertisers and shoppers.

The opposite risk matters too. A retailer that defines relevance only by the products it sells may miss partnerships that help customers complete a broader task. The near-endemic category is useful precisely because shopper needs often extend beyond the retailer’s assortment.

No universal list of acceptable industries can resolve this tension. A campaign that feels natural in one retailer’s environment could seem arbitrary in another. The retailer needs an approval process that gives commercial growth a clear boundary while leaving room for partnerships that genuinely serve customers.

Conclusion: Growth Beyond the Shelf

Non-endemic demand can extend Retail Media beyond established suppliers. The IAB guide gives the industry a clearer vocabulary for that expansion and a more honest account of its measurement requirements. Retailers still need to decide how those principles shape the campaigns they actually sell.

The next phase of growth may therefore depend less on how much inventory retailers can open to new advertisers than on the judgement they apply to each partnership.

The question is not whether a retailer can sell the placement.

It is whether the advertiser belongs in that moment, and whether both partners can demonstrate what the campaign achieved.