An evidence ledger for retail media competitors that separates facts from supplier claims

What to take away

Run one ledger per named entity and period, with every entry tagged as register fact, first-party claim, independent evidence or unknown.
A Companies House filing confirms a legal entity and its accounts; it cannot confirm retail media capability, reach or results.
Reviewing retail media suppliers with documentation, testing and independent evidence kept apart is the next step, because the ledger shows which claims still need a test.
Public access to a competitor page does not license copying its database, and self-selected reviews cannot produce a sentiment score.
Finish with an evidence gap table and mark routes with different units as non-comparable.

The comparison unit comes first

Pick one retailer-advertiser job and one environment. A shopper brand campaign running on a grocer's own site is a different unit from an off-site campaign bought through a network.

Write the job in one line, such as a household cleaning brand sold through England grocery stores.
Name the role under reviewretailer media owner, agency, platform, data supplier or measurement provider.
Set the research cut-off date and the England connection you require in evidence.
Keep the current internal or no-purchase route in the same table.

The IAB UK retail media definition marks a category boundary. It does not show that one supplier runs every environment or owns the inventory it resells.

Four evidence classes, one row each

Four evidence classes

Register factlegal name, company number, status and filed accounts, exactly as recorded.
First-party claimwhat the supplier says about its own service, geography, clients or method.
Independent evidencea regulator decision, published standard, official dataset or buyer-controlled test with a stated population and date.
Unknowneverything else, including price, reach, return and satisfaction for that exact entity and period.

Companies House states that its public register holds company information and makes certain records public. Use it for identity and filing history only.

Keep trading brands apart from the legal contracting party. Nectar360, Tesco Media and Insight Platform, Boots Media Group and Co-op Media Network are brand names. The contract sits with a named company.

Example: two filled rows for one England network

Two filled rows for one England network

Row A

Entity: Nectar360, described publicly as Sainsbury's retail media and loyalty business
Evidence class: First-party claim
Source and date: The supplier's own service page, with the access date recorded
What it establishes: The business describes itself as selling retail media to advertisers
What it does not establish: Audience reach, incremental sales, campaign performance or inventory ownership
Status: Claim only, excluded from benchmark columns

Row B

Entity: Sainsbury's Supermarkets Ltd
Evidence class: Register fact
Source and date: Companies House public register, with the filing date recorded
What it establishes: A legal entity, number, status and filed accounts exist
What it does not establish: Capability, commercial terms, results or customer satisfaction
Status: Foundation row, not a capability test

A filled row is still a starting point. Before you stack Nectar360 against Tesco Media and Insight Platform, settle which retail media route your case actually uses, since on-site, off-site and in-store carry different units.

Reviews and supplier claims in separate rows

Hold supplier testimonials, platform reviews, regulator cases and buyer interviews in different rows.
Confirm quotation permission and context before any participant wording is published.
Do not score sentiment or popularity from an undisclosed or self-selected sample.
Record an open investigation as open, not as a finding.

The CMA's online consumer reviews case record shows current enforcement and guidance activity. It does not rate any named retail media supplier.

A retailer's own customer review describes a shopping trip unless the wording addresses the media service directly. A retail media service standards note explains why the commercial unit has to be agreed before figures are compared.

England sources to cite beyond Companies House

A ledger row without a dated source is an opinion.

Add IAB UK for category and measurement vocabulary, the CMA for competition and review cases, the ICO for lawful data handling and direct marketing, and the ASA for the advertising codes behind in-store screens. BSI covers standards work, the ONS publishes retail sales and internet usage data, and the IPO explains database rights.

Cite each one for the point it actually settles.

Common questions

What four evidence classes does the ledger separate?

Register fact, first-party claim, independent evidence and unknown. Every row carries the named entity, the exact service and the period, so the class stays valid.

Can a Companies House filing prove retail media capability?

No. It confirms a legal entity, its number, status and filed accounts. Capability, reach and results need a separate, dated source.

How should reviews and testimonials be recorded?

Give each its own row, note permission and context, and never turn a self-selected sample into a sentiment score. An open CMA or ASA case stays open until it is decided.

What limits apply to copying a competitor website?

Copyright and database rights apply to contents and to the original selection or arrangement. Public access is not a licence to reproduce a competitor's collection.