Media audit

Media auditors should be able to clearly demonstrate to advertisers that both their organization and personnel possess the required expertise and experience — not only to understand the complex media buying ecosystem, but also to deliver credible and relevant evaluations of agency performance.
For multi-market audits, auditors should be ready to demonstrate sufficient geographical coverage.
Helpful documentation includes agency/client references, a client list (subject to confidentiality agreements), team breakdown by country, and/or information about cooperation with local partners.

Strict processes must be in place to protect sensitive data provided by agencies.
A Non-Disclosure Agreement (NDA) is required between the auditor and the agency.
The NDA must cover all technological platforms and any third parties involved.
If affiliated companies are engaged in the audit, they must also be covered by the NDA.
All data provided (e.g. pricing, strategy, contracts) must be used solely for the purpose of the audit.
Audit results may only be shared with the advertiser and the audited agency.

Some audit companies may also provide services that compete with media agencies. Any such potential conflicts of interest must be disclosed transparently to both the client and the agency before the audit begins.
It is recommended that auditor compensation is not linked to audit outcomes.
If the auditor provides competing services, full physical, personnel, process, and data separation between internal business units must be ensured.

Agencies work with licensed data sources (e.g. media research systems), which are protected by copyright.
Auditors and advertisers must respect the license restrictions that apply to these data sources.
Auditors should ideally hold their own licenses for access to market data and relevant software tools.

Auditors and agencies should agree on the audit timeline and scope before the process begins.
The schedule should include time for finalizing and signing the NDA.
Deadlines should be fair, reasonable, and allow flexibility for adjustments — e.g. changes to templates, additional auditor requests, or unforeseen delays outside either party’s control.

Auditors should clearly disclose the methodology used for calculations and data analysis.
Comparisons must take into account market specifics, seasonality, quality, and targeting.
Only relevant and comparable data sources should be used for benchmarking.

Auditors should provide advertisers and agencies with detailed information on the composition of their benchmarking sample (number of campaigns, markets, media types, quality, etc.).
The sample should be sufficiently robust and representative to deliver meaningful and relevant results.
Open dialogue around the composition of benchmarking pools helps ensure objectivity and credibility.

The same principles that apply to audits — confidentiality, respect for contracts, and fairness — should apply to media pitch processes.
Data requests must be appropriate in scope and covered by NDAs.
Auditors should provide agencies with clear briefing materials and templates to prepare their proposals.
Pricing evaluations should account for market specifics (e.g. seasonality, inventory quality, media mix).
If proprietary data platforms are used, agencies must be provided with clear guidance and/or training.
Agencies should be allowed to submit data in their standard formats.
The evaluation methodology should be transparent and included as part of the RFP.

You can access the full Global Third-Party Media Consultancy & Auditing Guidelines here: https://eaca.eu/wp-content/uploads/2025/04/Media-Auditing-guidelines-EACA-2025.pdf.pdf