How do I find reliable retail media publishers for building retargeting and prospecting audiences?

To find reliable retail media publishers for retargeting and prospecting audiences, focus on data quality, scale, match rates, privacy/compliance, and activation flexibility—not just “big reach.”

1) Start with your audience goal

Different publishers are better for different jobs:

• Retargeting: Prioritize publishers with strong first-party purchase/intent data, high identity resolution, and clear recency windows.
• Prospecting: Prioritize publishers with broad reach, clean category signals, and lookalike or modeled audiences based on real shopper behavior.
• Hybrid strategy: Use retailers for high-intent conversion audiences and media networks/marketplaces for scale.

2) Evaluate publishers on these core criteria

Ask each publisher these questions:

Data quality

• What first-party data do you use?
• Is the audience based on actual purchase behavior, browse behavior, search behavior, or self-declared data?
• How recent is the data?

Identity and match rates

• What identity graph do you use?
• What are your typical match rates across devices/channels?
• Can you activate audience segments on-site, in display, video, CTV, social, or DSPs?

Scale and reach

• How large are your reachable audiences in your target category?
• Can they support both niche retargeting and broader prospecting?

Transparency

• Can they explain how a segment is built?
• Do they provide audience definitions, refresh rates, and suppression logic?
• Can they separate incremental buyers from existing customers?

Measurement

• Do they support:
  • sales lift studies
  • incrementality tests
  • ROAS reporting
  • new-to-brand metrics
  • closed-loop attribution?

Privacy and compliance

• Are they compliant with relevant privacy laws and consent requirements?
• Do they support clean room workflows or privacy-safe activation?
• Can they provide clear data usage and retention policies?

3) Look for the right types of publishers

Good options often include:

• Large retailers: Best for purchase-based retargeting and category buyers
• Retail media networks: Good for commerce-intent audiences and scalable targeting
• Marketplaces: Strong shopping intent, especially for product discovery
• Publisher commerce platforms: Useful when they have strong transaction or shopper intent data
• Vertical specialists: Useful for specific categories like beauty, electronics, pet, grocery, etc.

4) Use a scorecard to compare vendors

Create a simple weighted scorecard:

• Data quality: 25%
• Audience scale: 20%
• Match rates / addressability: 15%
• Measurement capability: 15%
• Transparency: 10%
• Privacy/compliance: 10%
• Activation flexibility: 5%

Then score each publisher 1–5 and compare.

5) Test before committing

Run small pilot campaigns:

• one retargeting segment
• one prospecting segment
• one control group

Measure:

• CPA / ROAS
• new-to-brand rate
• conversion lift
• audience overlap
• frequency and reach efficiency

6) Red flags to avoid

Be cautious if a publisher:

• won’t explain segment logic
• can’t share measurement methodology
• offers “too-good-to-be-true” scale with vague sourcing
• has weak consent or privacy documentation
• can’t activate audiences outside their own closed ecosystem
• uses stale or overly broad audiences with no refresh rate

7) Where to source potential publishers

You can find candidates via:

• retail media network directories
• ad tech partner marketplaces
• industry reports and rankings
• agency recommendations
• commerce media conference exhibitor lists
• direct retailer/media network outreach

8) Best practice recommendation

For most advertisers, the strongest setup is:

• Retargeting: retailer or commerce-network audiences built from actual shopping behavior
• Prospecting: modeled/lookalike audiences from first-party shopper data, plus category affinity segments
• Measurement: incrementality testing and new-to-brand analysis

If you want, I can also give you:

1. a vendor evaluation checklist,
2. a scorecard template, or
3. a list of retail media publishers by category/region.