At a glance
A real-time tracking-health alert that fires when Criteo’s One Tag is firing on your site but failing to set or persist a first-party cookie on a meaningful share of sessions. Criteo’s entire retargeting model lives or dies on first-party signal: every PDP view, basket-add, and abandonment event the One Tag captures is what fills the retargetable audience pool for the next sync. When the tag fires without a cookie set, that signal is lost, the usual cause is Safari ITP or browser privacy enforcement catching up, and the visible consequence is an audience that quietly shrinks at the next audience refresh. This card catches the tag-without-cookie pattern in the hour it starts, before the shrinking audience shows up as a ROAS or conversion drop days later.
Calculation
Calculated automatically from your Criteo data. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading.Worked example
A US apparel DTC retailer with a heavily iOS / Safari audience deployed a storefront theme update on 09 Jun 26. The Criteo One Tag is present on every page. The card watches the share of sessions where the tag fires but no cookie persists.
What the pattern tells you:
- The breach starts exactly at the theme deploy. A sharp step-change aligned to a release almost always means a code-level regression: the cookie consent banner now blocks the tag, a cookie domain or SameSite attribute changed, or the tag moved behind a deferred script that fires after the page navigation completes. This is an engineering fix, not a Criteo settings change.
- A gradual creep instead of a step would mean ITP, not a deploy. If the rate climbed slowly over weeks with no release, that is Safari ITP enforcement tightening on your traffic as cookie lifetimes get capped. The fix there is different: deploy first-party identity and server-side signal rather than patch the tag.
- The tag is still firing. That is what makes this subtle. A naive tag-presence check would show green because the tag fires; the failure is in cookie persistence, which is invisible without this card. A marketer watching ROAS would only notice three to five days later when the shrunken audience syncs and retargeting efficiency drops.
- The downstream clock has started. Every breached hour is signal not captured. The retargetable pool feeding the next audience sync is smaller than it should be, so expect the retargeting ROAS card to soften within a few days if this is not fixed quickly.
- First action is to reproduce in a Safari private window and a consent-rejected session. That tells you whether the cause is consent-banner blocking, a cookie-attribute regression, or genuine ITP. Reproduce, fix, and watch the rate fall back toward the single-digit baseline.
- Sharp step-change at a release = code regression, roll back or patch the tag.
- Slow creep over weeks with no release = ITP enforcement, deploy first-party identity.
- Rate high only on Safari / iOS split = ITP, expected, mitigate rather than fix.
- Rate high across all browsers after a consent-tool change = consent banner blocking the tag.
- Rate returns to baseline after the fix = signal capture restored, audience recovers at next sync.
Sibling cards merchants should reference together
Reconciling against Criteo
Where to look in Criteo’s own dashboard:Criteo Management Centre → Audiences → Audience size / match rate, and the One Tag health view under Assets → Tags, filtered to the same advertiser account.Criteo’s Audiences view shows retargetable audience size and match rate over time, the lagging indicator that this card predicts. When the tag-without-cookie rate breaches here, expect Criteo’s reported audience size to step down at the next sync. Criteo’s own tag-health surface reports whether the tag is firing, but it is weaker at distinguishing fired-but-no-cookie from fired-and-cookied, which is exactly the gap this card closes. Reconcile by correlating a breach window on this card with a subsequent dip in Criteo’s reported audience size or match rate. Why our number may legitimately differ from Criteo itself: A gap is expected here because the two surfaces measure different points in the chain.
Cross-connector reconciliation:
This card is Criteo-only. Tracking-health failures often share a root cause with other on-site tags, so the useful comparison is operational rather than mathematical: