From Blockgraph to Open ID to IFA and seller-defined audiences, we look at the best privacy-focused ID solutions on the market as part of The Drum\u2019s Data & Privacy Deep Dive.The connected TV (CTV) media ecosystem doesn\u2019t rely on cookies, but it would be wrong to think the reduction of third-party data won\u2019t affect premium video. TV advertisers need to start paying attention to privacy changes that will impact them and find solutions to invest in.Current privacy regulations mean 30% of audiences are non-addressable, but incoming consent regulation and the death of the cookie mean that, by 2024, 75% of audiences will be non-addressable.Giovanni Gardelli, vice-president of ads data products at Yahoo, calls for major investment in identity solutions for CTV. Identity impacts nearly every advertising use case, from frequency capping and audience targeting to measurement, he explains.\u201dHowever, many of those IDs will depreciate over the next two years. Addressability will continue to shrink in mobile and web throughout 2023 and 2024 and it is important that CTV advertisers and publishers start paying attention to how it will impact them.\u201dThe quality of measurement on CTV is at risk when the addressable supply shrinks. When a viewer sees an ad on their connected TV and then purchases a product, the conversion would be registered on a mobile or computer, not the TV.Gardelli says: \u201cTo be able to measure ad effectiveness in CTV, purchases on non-TV devices need to be able to be tied to ad exposures on CTV. This is why omnichannel solutions and first-party data are critical.\u201dSo, what solutions are on the market?A lot of CTV-specific solutions aren\u2019t cut out for cross-media targeting and measurement, which can mean that advertisers aren\u2019t able to gauge the true impact of a campaign. The best solutions on the market all avoid treating CTV as a siloed channel, and instead as part of a media mix.\t\tBlockgraph ID was born out of a partnership between Comcast, Charter, and ViacomCBS. It is more of a CTV-first solution rather than CTV-specific, given that adoption has mainly been from CTV supply. One of the biggest benefits of Blockgraph ID is that it unifies linear and set-top box identity, which is fragmented in the TV space. While Blockgraph ID offers better identity resolution and targeting, it doesn\u2019t solve the biggest use case when it comes to identity solutions for CTV - measurement. \t\t\tOpen ID is part of Open AP. Similar to Blockgraph ID, while Open ID allows for the unification of identity in linear and digital, it is not an omnichannel ID capable of solving for holistic, cross-campaign measurement. \t\t\tIFA is an ID specification from IAB Tech Lab and can be a device- or publisher-specific ID. While IFA has been in use for many years, it does remain a viable identifier for CTV \u2013 with the caveat that, just like other CTV-specific IDs, it cannot solve for omnichannel measurement.\t\t\tSeller-defined audiences give publishers the responsibility of segmenting audiences. First introduced by the IAB Tech Lab\u2019s Project Rearc, it can provide a privacy-centric way for publishers to use their first-party data. It\u2019s a key development for a number of reasons, including publishers\u2019 desire for more control over their audiences, standardized systems and more transparency. \t\tStefanie Briec, a director and head of demand sales at FreeWheel, says the audience and regulator views on data privacy will \u201cshape the future of premium video advertising.\u201d She urges TV advertisers to keep industry regulators front of mind as they develop new tools for buyers and sellers: \u201dEnsuring advertising capabilities are future-proofed and solutions are interoperable is essential for making premium video accessible to buyers and monetizable for sellers in a privacy-centric landscape.\u201dThe end of the third-party cookie has shown marketers how conscious viewers have become about privacy, Briec explains. To maintain viewer trust in premium video advertising, she says it is critical for advertisers to be \u201ctransparent about data practices and educating audiences about the value exchange.\u201dFour crucial things to remember about CTV and identity\t\tNot all IDs are created equal \u2013 many only focus on solving a portion of the problem.\t\t\tAddressability will continue to have a significant effect on CTV targeting and measurement.\t\t\tIn an evolving ecosystem like adtech, interoperability is important to preserving and growing identity solutions across different channels.\t\tViewers watch across multiple devices, so identity solutions must cater to that.For more on how the world of data-driven advertising and marketing is evolving, check out our latest Deep Dive.