IAB Australia last year named 47 identity providers that advertisers are working with, in an explainer guide about identifiers.
Criteo, Equifax, Experian, Eyeota, Google, ID5, InMobi, Lifesight, LiveRamp, Lotame, Meta, Near, Oracle Data Cloud, Unified ID 2.0, Yahoo, Adobe, Adara, Adstra, AlikeAudience, Amperity, Audience Project, BiGDBM, Britepool, Crimtan, Datonics, DigiCenter, FullContact, Infutor, IRI, mParticle, Media Wallah, Neustar, OneData, Salesforce, Retargetly, Semcasting, ShareThis, SirData, TailTarget, The ADEX, Throtle, TrasUnion, Treasure Data, TrueData, Valassis, Weborama, Zeotap are the named as identity providers.
According to IAB Australia, identifiers help fight fraud, improve brand safety, deliver a better experience to consumers, and support measurement and attribution.
In the guide, IAB Australia used 6 criteria to evaluate the identifiers: data sources, base identifiers, consent type, availability and addressability, interoperability and prerequisites.
There are two type of IDs when it comes to data sources. The IDs that work with owned & operated inventory and data like Google, Meta, and Yahoo. And identifiers that work across global publishers & data suppliers like ID5, Criteo, and LiveRamp.