[MO-Thibault]

Summary

Both Prebid analytics add-ons, the V1 prototype (lib/addons/prototypes/analytics.js) and V2 (lib/addons/prebid/analytics.ts), now report which competitor identity vendors put EIDs into each auction, next to the existing LiveIntent field: IntentIQ, GrowthCode and TransUnion.

• New auction fields intentiqEIDs, growthcodeEIDs and transunionEIDs: the EID sources each vendor delivered, same shape as liveintentEIDs. Per-bidder iiqSources, gcSources and tuSources sit next to liSources.
• LiveIntent detection now also matches source === "liveintent.com". LiveIntent's main ID carries no ext.provider, so the old filter missed it.
• The rules live in one COMPETITOR_EIDS table at the top of each file. The two copies are identical.

V2 port

• Master is merged into the branch to pick up analytics: report LiveIntent EIDs in V2 prebid analytics #364, which added LiveIntent to V2. The V2 port builds on it.
• In V2 the rules run on the EIDs before the source dedupe, like analytics: report LiveIntent EIDs in V2 prebid analytics #364's LiveIntent check. So a competitor EID is not hidden by another EID with the same source.
• Documented in lib/addons/prebid/analytics.md.

Why

To measure our uplift against what else is enriching the same bid requests, we need to know when a competitor's IDs were present. Until now we could only see LiveIntent's partner IDs.

Detection rules

Vendor	Rule	Where observed
LiveIntent	source === "liveintent.com" or uids[].ext.provider === "liveintent.com"	Prebid libraries/liveIntentId/shared.js; Freestar auction
IntentIQ	matcher === "intentiq.com" or source === "intentiq.com"	Freestar auction (inserter: freestar.com, matcher: intentiq.com, mm: 5); source is what Prebid's intentIqIdSystem emits
GrowthCode	inserter, matcher or source is "growthcode.io"	essentiallysports.com, si.com, 5 of 7 GrowthCode sites checked
TransUnion	source === "neustar.biz" (Fabrick ID, no other tags)	Prebid fabrickIdSystem; Freestar sends it to all bidders on 9 of 11 sites checked (reuters, apnews, fortune, aljazeera, ...)

The tags come from each vendor's server, not from their client code, so they were confirmed on live pages. Some publisher wrappers strip inserter (MinuteMedia does on si.com), so each rule also checks matcher or source.

Known gaps

• When a wrapper strips the tags, IDs GrowthCode relays for other vendors (Acxiom, ID5, Criteo, Epsilon, Xandr) carry no GrowthCode marker and are not counted.
• LiveIntent's copy of the TTD ID uses the page's domain as ext.provider; not matched here.
• Fabrick is missing from a new visitor's first auction on Freestar (it resolves after the 100 ms auctionDelay), so transunionEIDs undercounts first auctions.

Overlap with #351

#351 edits the same per-bidder block and witnessData, in V1 and now also V2 (its page object). Whichever merges second needs a small rebase.

Test plan

• Ran COMPETITOR_EIDS against captured auctions: essentiallysports and si.com return GrowthCode sources only; an excerpt of a Freestar auction returns LiveIntent (liveintent.com, uidapi.com, openx.net) and IntentIQ (adsrvr.org, intentiq.com), with no match on Optable's own EIDs or the native TTD ID; a neustar.biz EID matches only the TransUnion rule
• V2 tests in lib/addons/prebid/analytics.test.ts (3 new): LiveIntent's main ID matched by source, IntentIQ/GrowthCode/TransUnion per bidder and at the auction level (including each rule's inserter/matcher/source variants), and no match on Optable's own EIDs
• pnpm test (583 passed after the master merge); pnpm build-lib passes; prettier --check clean
• After deploy, confirm intentiqEIDs, growthcodeEIDs and transunionEIDs appear in auction_processed (V1) and optable.prebid.auction (V2) events for a tenant known to run each vendor

🤖 Generated with Claude Code

[mosherBT]

We can make this accept a param from wrappers so we don't have to constantly update this if new ones are on a page for certain tenants. Not blocking