Auditing Amazon DSP Attribution to Find Your True MER

DSP ROAS and business-level marketing efficiency answer different questions. Audit the report definitions before assuming the consoles counted the same sale twice or that view-attributed sales were caused by advertising.

Check the Attribution Scope

Current Amazon Ads documentation describes competition for attribution among specified brand ad products, with last-click priority over views. Sponsored Products for sellers has distinct attribution treatment. Therefore “DSP and all Sponsored Ads always double-count” is not a safe universal statement.

Amazon also applies view-eligibility/viewability conditions, with changes introduced in 2026. A banner merely loading out of view does not by itself establish an eligible view-through conversion.

Reconcile Comparable Measures

1. Record advertiser type, ad product, report metric, attribution window, and click/view treatment.
2. Align promoted-product and brand-halo scope.
3. Separate conversion dates from traffic dates and consider refunds and reporting lag.
4. Check whether the metric is deduplicated within the report scope before adding it to another report.

Calculate MER with a Defined Scope

Measure Causality Separately

MER is a useful financial guardrail, but price, product mix, organic demand, and stock can move it. AMC supports privacy-safe analysis and audience tools; it does not turn observed overlap into a randomized experiment. Seller Scale recommends using an appropriate incrementality test before making a causal claim about saved or wasted DSP spend.

Sources and Scope

The linked sources support the documented points above. Recommendations and hypothetical calculations are editorial guidance, not Amazon rules or promised results. Check the current requirements for your marketplace and account before acting.

• Amazon Ads attribution
• Amazon view-attribution update
• Amazon Marketing Cloud