In 2022, Google began changing the availability of the information available in User-Agent strings across their Chromium browsers. The change is to use the set of HTTP request header fields called Client Hints. Through this process, a server can request, and if approved by the client, receive information that would have been previously freely available in the User-Agent string. This change is likely to have an impact on publishers across the open web that may use User-Agent information today.
To explain what this change means, how it will impact the AdTech industry, and what you can do to prepare, we spoke with Nate West, our Director of Product.
What is the difference between User-Agents and Client Hints?
A User-Agent (UA) is a string, or line of text, that identifies information about a web server’s browser and operating system. For example, it can indicate if a device is on Safari on a Mac or Chrome on Windows.
Here is an example UA string from a Mac laptop running Chrome:

To limit the passive fingerprinting of users, Google is reducing components of the UA strings in their Chromium browsers and introducing Client Hints. When there is a trusted relationship between first-party domain owners and third-party servers, Client Hints can be used to share the same data.
This transition began in early 2022 with bigger expected changes beginning in February 2023. You can see in the above example, Chrome/109.0.0.0, where browser version information is already no longer available from the UA string on this desktop Chrome browser.
How can you use User-Agent device attributes today?
UA string information can be used for a variety of reasons. It is a component in web servers that has been available for decades. In the AdTech space, it can be used in various ad targeting use cases. It can be used by publishers to better understand their audience. The shift to limit access and information shared is to prevent nefarious usage of the data.
What are the benefits of Client Hints?
By using Client Hints, a domain owner, or publisher, can manage access to data activity that occurs on their web properties. Having that control may be advantageous. The format of the information shared is also cleaner than parsing a string from User-Agents. Although, given that Client Hints are not the norm across all browsers, a long-term solution may be needed to manage UA strings and Client Hints.
An advantage of capturing and sharing Client Hint information is to be prepared and understand if there is any impact to your systems and processes. This will help with the currently planned transition by Google, but also should the full UA string become further restricted.
Who will be impacted by this change?
Publishers across the open web should lean in to understand this change and any potential impact to them. The programmatic ecosystem supporting real-time bidding (RTB) needs to continue pushing for adoption of OpenRTB 2.6, which supports the passing of client hint information in place of data from UA strings.
What is Google’s timeline for implementing Client Hints?

Do businesses have to implement Client Hints? What happens if they don’t?
Not capturing and sharing with trusted partners can impact capabilities in place today. Given Chromium browsers account for a sizable portion of web traffic, the impact will vary for each publisher and tech company in the ecosystem. I would assess how UA strings are in use today, where you may have security concerns or not, and look to get more information on how to maintain data sharing with trusted partners.
We can help you adopt Client Hints
Reach out to our Customer Success team at tapadcustomersuccess@experian.com to explore the best options to handle the User-Agent changes and implement Client Hints. As leaders in the AdTech space, we’re here to help you successfully make this transition. Together we can review the options available to put you and your team on the best path forward.
Get in touch
About our expert

Nate West, Director of Product
Nate West joined Experian in 2022 as the Director of Product for our identity graph. Nate focuses on making sure our partners maintain and grow identity resolution solutions today in an ever-changing future state. He has over a decade of experience working for media organizations and AdTech platforms.
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Study reveals that brands with more mature identity programs were significantly more likely to be successful in achieving their key objectives Tapad, a part of Experian, a global leader in cross-device digital identity resolution and a part of Experian, has commissioned Forrester Consulting, part of a leading research and advisory firm, to conduct a new study that evaluates the current state of customer data-driven marketing and explores how marketers can use identity solutions to deliver privacy safe and engaging experiences, in an evolving data landscape. The study highlights the changing ground rules for digital marketing and the threat that poses to marketers’ ability to deliver against long standing KPIs and campaign goals. Nearly two-thirds (62%) of respondents said that the forces of data deprecation will have a significant (40%) or critical (21%) impact on their marketing strategies over the next two years. Among those surveyed, identity resolution strategies have surfaced as an opportunity to create more powerful customer experiences, with 66% aiming to have it help improve customer trust and implement more ethical data collection and use practices, while nearly 60% believe it will point the way to more effective personalization and data management practices. Although organizations are eager to implement identity resolution strategies, a complex web of solutions and partners makes execution a challenge. For example, respondents report using at least eight identity solutions on average, across nearly six vendor partners, and they expect that fragmentation to persist in the ‘cookieless’ future. Additionally, brands’ identity resolution technologies typically represent a patchwork of homegrown and commercial solutions. Eighty-one percent of respondents use both in-house and commercial identity resolution tools today, and 47% use a near-equal blend of the two. Despite the challenges, many brands have the foundation for a strong identity resolution strategy in place, and they are thriving as a result. Specifically, more mature brands were 79% more successful at improving privacy safeguards to reduce regulatory and compliance risk, 247% more successful at improving marketing ROI, and over four times more effective at improving customer trust compared to their low-maturity peers. Additional insights include: Marketers Are Increasingly Playing a Key Strategic Role Within the Organization, But There is a Mandate to Demonstrate Value. Nearly three-quarters of respondents in our study agree the marketing function is more strategically important to their organization than it used to be, while almost two-thirds agree there’s more pressure than ever to prove the ROI or business performance of their activities. Consumers Expect Brands to Deliver Engaging Experiences Across Highly Fragmented Journeys: Tapad, a part of Experian found that 72% of respondents agree that customers demand more relevant, personalized experiences at the time and place of their choosing. At the same time, 67% of respondents recognize that customer purchase journeys take place over more touchpoints and channels than ever, and 59% of respondents agree that those journeys are less predictable and linear than they once were. Marketing Runs on Data, But the Rules Governing Customer Data Usage are Ever-Evolving: According to the study, 70% of decision-makers agree that consumer data is the lifeblood of their marketing strategies – fueling the personalized, omnichannel experiences customers demand. At the same time, 69% of respondents recognize that customers are increasingly aware of how their data is being used. At least two-thirds agree that data deprecation, including tighter restrictions on data use (66%), as well as operating system and browser changes impacting third-party cookies (68%) means that legacy marketing strategies are unlikely to remain viable in the long-term.“ Our latest survey findings give us a better understanding of how our customers and other companies around the world are trying to master the relationship between people, their data and their devices,” said Mark Connon, General Manager at Tapad, a part of Experian. “This research shows why it's fundamental for the industry to continuously work to develop solutions that are agnostic. Tapad, a part of Experian has worked tirelessly to deliver on this with our Tapad Graph, and by introducing solutions like Switchboard to help the evolving ecosystem and in turn helping customers reap the benefits of better identity in both short and long-term.” The study is founded on an online survey of over 300 decision-makers at global brands and agencies, which was fielded from March to April, 2021. Data deprecation and identity are fast-developing, moving targets, so this study delivers targeted insights and recommendations for how to prepare for coming shifts in customer data strategies – whether they manifest tomorrow or a year from now. Get in touch

Third-party cookies have been a crucial component in people-based advertising and digital identity. With Google's recent announcement of delaying third-party cookie deprecation to 2024, the industry has more time to rethink how to effectively identify and communicate with consumers when the time comes. Preparing for cookie deprecation Solving for the post-cookie world is mission critical, particularly as consumer expectation for a relevant digital experience is heightened. We’ve seen a number of industry participants, including brands, publishers, data providers and technology platforms, work around the clock to find an alternative to third-party cookies—one that amasses the same scale and reach but also maintains consumer privacy. In fact, industry insights echo that sentiment. According to a white paper from Winterberry Group, Collaborative Data Solutions: The Evolution of Identity in a Privacy-First, Post-Cookie World, sponsored in part by Experian, one of the most frequently heard comments was the urgency for the industry to develop post-cookie, privacy compliant solutions that work in a more integrated manner. And if there was one overarching position regarding the research into the future of identity, it’s that collaboration is key. Participants in the white paper expressed that with the elimination of third-party cookies, there will be a surge in collaborative solutions across and within companies to accommodate changes in the digital marketplace. Collaborative data solutions must move beyond new post-cookie identity replacements and encompass more holistic approaches, including first-party data. First-party data sharing Currently, 64.3 percent of organizations in the US collaborate with other organizations to share first-party data for insights, activation, measurement or attribution, and 16.7 percent in the U.S. have plans to. Virtually all US companies surveyed were aware of the option to collaborate with other organizations and expressed openness to discussions around sharing first-party data. What is the solution to third-party cookie deprecation? The deprecation of third-party cookies is creating a shock in the marketing and advertising world because there has been an over-dependence on one type of identifier. Therefore, the solution to identify consumers across the digital ecosystem will not come from a single replacement for third-party cookies. Instead, it will rely on a combination of solutions, including collaborative data between organizations and implementation of proprietary first-party data strategies, as well as a framework that can connect all these touchpoints together. Experian can help you navigate the cookieless future Experian is focused on building a more effective advertising ecosystem that promotes the interoperability of digital touchpoints while enabling and fostering new innovations in a privacy forward way. Contact us today and get started with building connected identity in the ever-changing data landscape. To learn more, watch the recording of our webinar with The Vitamin Shoppe where we discuss identity and how you can drive more addressable audience strategies amidst diminishing data signals. Get in touch

As today’s digital landscape gets more and more complicated there are more ways for brands to connect with users and drive purchases and more ways for ad tech to target and measure those touch points. As in-person shopping picks up steam due to the re-normalization of society post-COVID 19; the connection between digital ads and in-person purchases needs to be made once again. With the rise of Connected TV throughout the pandemic there are even more digital opportunities to target a user. But how do you make sure that those brand engagements are captured and correctly attributed to offline purchases and conversions? The answer lies in a holistic identity resolution strategy. Cross-device identity resolution with The Tapad Graph connects the identifiers and devices of individuals within a household to each other; enabling targeting, frequency capping, extension, segmentation and measurement or attribution between devices; including Connected TV and hashed (privacy-protected) email addresses along with Cookies, Mobile Ad Ids and IP Address. Brands can join their first-party data to The Tapad Graph to execute strategies that connect online and offline data for pre, mid and post-campaign efficiencies. Let’s imagine a scenario in which an outdoor retail brand is targeting users watching specific content on a Connected TV device. Powered by identity resolution, they start with a general ad on CTV and continue targeting down individual paths with each user. When one of them converts in store and makes a purchase; the outdoor retailer can connect that action through location and in-store traffic data with the cross-device identity resolution used to execute the digital campaign. Now the actions of the user online and offline are resolved for more accurate measurement and attribution after the campaign ends. But it doesn’t stop there– the brand's CRM data can be reactivated for the next digital campaign and leveraged to capitalize on the most effective media mix for the user who made the purchase previously. These combined insights can be invaluable in shaping up future campaign strategies with geo-contextual ads, recommended additional products and personalization to help drive more conversions and purchases in-store or online. As in-person shopping picks back up and marketers are tasked once again with balancing online and in-store KPIs, the right identity resolution strategy can unlock necessary efficiencies for retailers, ad tech vendors and agencies tasked with supporting these initiatives. Get in touch