The uncertain future of third-party cookies—especially with their phase-out in browsers like Safari and Firefox, along with Google Chrome’s upcoming Privacy Sandbox—has cast doubt on the effectiveness of third-party cookies in identity resolution. Yet, identity resolution is still a vital part of customer marketing strategies, enabling brands to develop a unified customer view that supports powerful marketing tactics like real-time personalization, remarketing, and insightful data analytics.

In this post, we’ll explore identity resolution in today’s data landscape and discuss strategies to future-proof your approach to identity resolution.

Understanding Identity Resolution in the Modern Digital Landscape

What is Identity Resolution? Identity resolution is all about connecting the dots between different identifiers that show up across the devices and websites you interact with to build a single, unified picture of each customer. With data privacy taking center stage today, identity resolution lets you learn about and engage with your customers on a more personal level while staying respectful of their privacy and consent preferences. By sticking to these principles and gathering data directly from your customers, you can shape accurate customer profiles that drive things like real-time personalization.

But let’s face it—we’re stepping into a cookie-less era. Major browsers like Safari and Firefox have already ditched third-party cookies, and Google’s upcoming Privacy Sandbox for Chrome is about to further limit tracking. Add the popularity of ad blockers and increasing browser restrictions to the mix, and keeping track of your customers’ identities just got a lot trickier. Privacy regulations like GDPR and CCPA have also flipped the script on how you can gather and use data, demanding greater compliance.

So, first-party data has become more critical than ever. With third-party data getting harder to come by, first-party data is now essential for everything you want to achieve—identity resolution, analytics, personalization, and more. It allows you to keep tabs on how customers interact with you across your website, apps, and even in brick-and-mortar stores. By pulling this data together, you can create a cohesive customer profile and then share that information with other systems, like customer data platforms (CDPs), data management platforms (DMPs), marketing tools, and analytics.

Building and maintaining accurate, up-to-date customer profiles is a must these days. But as third-party cookies fade away, achieving this is getting more challenging.

The Challenges of Identity Resolution without Third-Party Cookies

The decline in reliability and eventual phase-out of third-party cookies is a big hurdle for modern brands. There are a few specific challenges they’re up against. First, there’s data fragmentation. Customers today engage with your brand on all kinds of devices and platforms, leading to fragmented identities. If a customer switches from their phone to their desktop or bounces between a subdomain and your main site, the chances of data fragmentation shoot up, especially depending on the tracking tech you’re using. This fragmented data needs to be unified to create a full picture of each customer, and without third-party cookies, that’s not as simple as it used to be. Thankfully, there are new technological options that can help bridge this gap.

Another major challenge is privacy regulations. Laws like GDPR and CCPA have set strict rules on how you handle data, demanding that customer privacy is respected at every stage. For identity resolution to comply, all data collected must be gathered responsibly and with consent, prioritizing customer privacy. It’s not just about following the rules to avoid fines; it’s about building trust with your customers. People today expect brands to use their data thoughtfully and respectfully, and your data governance strategy plays a huge role in achieving this.

Then, there’s the whole probabilistic versus deterministic matching debate. Deterministic matching uses direct identifiers—like email addresses—to accurately match customer data. It’s reliable, but it depends on user-provided, first-party data and requires consent. Probabilistic matching, on the other hand, uses statistical analysis to link identities. It might rely on things like IP addresses and device types, which are less precise but can help fill in the blanks when direct identifiers aren’t available. Both approaches have their strengths, but deterministic methods are generally more privacy-compliant because they focus on consented first-party data.

Ultimately, overcoming the challenges of identity resolution means doubling down on first-party data collection methods. It’s about adapting to new strategies and finding innovative ways to unify your customer data without relying on third-party cookies.

Modern Solutions for Identity Resolution Challenges

Despite the hurdles, identity resolution in today’s digital landscape does have some advanced technological solutions. There are several approaches that can help, starting with the use of a Customer Data Infrastructure Platform, or CDI. CDIs provide a structured framework for collecting, unifying, and managing customer data from various sources in real-time. This approach lets you gather data reliably without needing third-party cookies. CDIs leverage first-party data from all your platforms and integrate with different tools, such as CDPs, DMPs, CRMs, and Marketing Automation Platforms. Acting as the center of a hub-and-spoke model, the CDI collects and distributes data while ensuring it’s cleaned and compliant at every step. Only customer data with consent is shared, making sure privacy regulations are respected throughout the data distribution process.

Another key technology is server-side tracking. Unlike client-side tracking, server-side solutions provide increased security and control over customer data. Here’s why: this method uses a first-party script, meaning you don’t rely on third-party vendor scripts loaded in the browser. Instead, server-side tracking uses a single, domain-matching script to collect information. Once this data is collected, it’s sent to a secure server, which then distributes it based on defined logic. Server-side tracking can enforce consent at the data collection stage, helping to normalize and manage data. It also controls what information gets shared with various vendors, even providing anonymous identifiers when needed to protect personally identifiable information.

At the end of the day, server-side tracking and a CDI work well together by collecting and distributing data in a way that’s both compliant and secure. These tools integrate seamlessly with existing tech stacks—an essential factor for effective identity resolution. For identity resolution to work, you need a unified customer profile shared across multiple platforms. With this setup, you can securely share customer data with CRMs, CDPs, marketing automation platforms, and analytics tools. And no matter which platform you’re logged into, you’ll be seeing the same, consistent view of each customer.

Key Identity Resolution Techniques

How do we actually identify users using various data collection points? Let’s break down a few foundational techniques:

• First-Party Data Collection Methods
• Visitor Stitching
• Cross-Device Identification

First-Party Data Collection Methods

First-party data collection is at the core of modern identity resolution. This is data gathered directly from user interactions on channels you control—things like website form submissions, app usage, e-commerce interactions, and even in-store experiences. These methods are particularly valuable because you’re working with consented, privacy-compliant data that you can trust for its accuracy.

What’s often overlooked is just how valuable first-party data is due to its real-world connection between you and your customers. Your team can analyze this data to uncover customer intent and preferences based on these direct interactions. Unlike third-party data, you control the mechanisms used for collection, allowing you to interpret these interactions in terms of overall brand engagement. This data is highly applicable to personalization, analytics, and other marketing initiatives, as it’s not only relevant but often carries implicit consent.

Visitor Stitching

Visitor stitching is a bit more technologically challenging, as it involves combining user data from multiple interactions across different properties—think of a customer visiting your mobile app, browsing your website, or even navigating across multiple domains you own. Stitching all these interactions together into a unified customer profile requires consistent tracking techniques. This is where server-side tracking becomes invaluable. With server-side tracking, you can have first-party scripts running on your site, sending data back to your servers, where you can then perform identity resolution.

Each interaction collected through visitor stitching acts as a clue, gradually revealing more about your customers’ preferences and behaviors. But, as these interactions come in fragmented pieces, there needs to be a process for weaving them together into a single, cohesive view. This is crucial for brands with multiple digital touchpoints, as it enables you to accurately interpret and understand customer behavior. In a world where customers interact with brands in so many different ways, stitching these touchpoints together lets you create more personalized experiences and a better overall user journey.

Cross-Device Identification

Today’s customers are device-hopping all the time—they may research on their phone over Wi-Fi, switch to mobile data, then continue on a desktop computer, and finally, even revisit on a work device. This varied experience makes cross-device identification more important than ever. By using first-party and server-side data tracking, brands can identify users consistently across multiple devices, building a complete view of their journey.

Cross-device identification is all about recognizing that while these interactions happen on different devices, they’re all part of one customer journey. Customers don’t see these touchpoints as disconnected—they see them as seamless interactions with your brand. First-party data collection, combined with server-side tracking, allows you to link activities across devices without the need for third-party cookies, making it a far more reliable tracking method. This technique gives you valuable insights into how customers move through various channels, ultimately helping you provide personalized interactions and deliver relevant advertising to them.

Use Cases for Identity Resolution

So, how can marketers really get the most out of identity resolution? Let’s break down three main use cases where this tech makes a massive impact: personalized marketing campaigns, improved ad attribution, and enhanced customer insights.

• Personalized Marketing Campaigns
• Improved Ad Attribution
• Enhanced Customer Insights

Personalized Marketing Campaigns

Having a unified view of each customer is exactly what tools like Customer Data Platforms (CDPs) are all about. CDPs let you pull together customer data from multiple sources, allowing you to map out the customer journey in real-time. When you add in a CDI or server-side tag manager, suddenly you’re able to gather, process, and distribute this data instantly. Now you can fire off real-time personalized campaigns—like triggered email sequences based on interactions with your site or even ultra-relevant remarketing ads that target specific customer interests.

Here’s the thing: customers want personalized experiences. They don’t want to be lumped into broad segments—they expect to be treated as individuals. Identity resolution lets you connect the dots and identify customers uniquely, allowing for targeted messaging that drives better engagement and higher conversions.

Improved Ad Attribution

One of the biggest pain points in digital advertising is figuring out what’s actually working. How do you know if those clicks on your latest ads are turning into meaningful interactions? Identity resolution helps by letting you track ad engagement with far more accuracy. With server-side tracking, you can pull data from landing pages and link it back to the ad campaigns that brought users there. You’re then able to distinguish between click-throughs and view-through conversions and get a clearer sense of which ads truly resonate with your audience.

For brands heavily relying on digital ads, understanding what’s driving performance is essential. Without this visibility, many brands are essentially flying blind. Identity resolution connects ad data to customer actions, giving you the insight needed to optimize ad spend and align marketing efforts with sales goals.

Enhanced Customer Insights

The more you know about your customers, the better. Identity resolution doesn’t just help with marketing—it also gives you a deep view of customer preferences, behaviors, and needs. Let’s say you’re a tech company. By tracking a user’s journey from your website to your app, you can make data-driven decisions about product features and user experience. Or if you’re in customer service, you can look at support interactions and tailor improvements to serve your customers better.

By piecing together interactions across touch points, identity resolution empowers strategic decisions based on real customer journeys. This technology makes it possible to anticipate needs, build personalized experiences, and nurture long-term customer relationships by truly understanding their entire experience with your brand.

Best Practices for Implementing Identity Resolution Strategies

When it comes to identity resolution, everything hinges on compliance with your data governance strategies. Privacy-first, compliant data isn’t just valuable; it’s essential. Collecting data with a privacy-first strategy is crucial, and it starts with getting consent at the moment of collection. Once you have that consent, your responsibility is to use the data safely and securely. Modern brands that prioritize this—and have mechanisms in place to align with regulations like GDPR and CCPA—can leverage their data with confidence.

Leveraging CDIs for Data Agility

Customer Data Infrastructures (CDIs) are flexible tools that can help brands navigate shifting privacy laws and data trends. CDIs enable data agility, allowing you to handle different regulations and consent methodologies while also distributing data efficiently across your various platforms. Think of CDIs as not just data collectors but also as distribution engines: they gather data from your website, mobile app, or any first-party channels and push it out to the platforms that need it, like your CDP or marketing automation systems. By combining a privacy-first approach with the flexibility of a CDI, you’re setting up a best-practice framework for identity resolution.

Ongoing Testing and Optimization

Finally, maintaining an ongoing testing and optimization protocol is a must. Identity resolution isn’t a set-it-and-forget-it process. Does a deterministic matching model work best for your needs? Or does probabilistic matching provide valuable insights by filling in gaps? Finding the right balance between deterministic and probabilistic data takes a bit of trial and error. Regularly tweaking and testing these approaches will ensure that you’re making the most out of your data, improving the accuracy of customer profiles over time.

Ultimately, identity resolution is about more than just gathering data—it’s about responsibly collecting, managing, and using it to build trust, enhance personalization, and create a comprehensive customer view that evolves with your brand’s needs and privacy requirements.

Future Trends in Identity Resolution

Several trends are paving the way for the future of identity resolution, and these shifts are worth paying close attention to.

AI and Machine Learning

The potential of AI and machine learning in this space is immense. These technologies are transforming both probabilistic and deterministic matching by analyzing massive amounts of data to reveal patterns and connections we wouldn’t otherwise see. Machine learning, in particular, is just getting started—it’s learning to become faster, smarter, and more accurate. As these tools continue to evolve, the accuracy and effectiveness of identity resolution will reach new heights, reshaping what’s possible.

Regulatory Changes in Data Collection

Privacy regulations are tightening, and this trend shows no signs of slowing down. Brands need to stay on their toes to keep up with the latest standards. With data governance becoming more crucial, having a flexible strategy is key, along with technology that lets you pivot as new regulations come down the pipeline. The right setup allows you to adapt swiftly, keeping compliance measures fresh and minimizing risks.

The Rise of Zero-Party Data

Zero-party data—data customers intentionally share with you—brings a whole new level of precision to identity resolution. Unlike first-party data that’s observed, zero-party data is willingly given by the customer, making it incredibly valuable for personalization. This data type isn’t just a complement to first-party data; it’s a direct line to understanding customer intent. With zero-party data, you’re not just interpreting behavior—you’re getting insights straight from the source, enabling more accurate targeting and building stronger customer relationships.

Navigating a Cookie-less Future with CDI and Server-Side Solutions

Navigating a cookie-less future is top of mind for many brands right now. While third-party cookies may be fading, the digital data ecosystem is richer than ever. The rise of first-party data and the increasing use of zero-party data paint a vivid picture of customer journeys, allowing brands to connect more deeply than before. The linchpins of data collection and usage in this new era are Customer Data Infrastructures (CDIs) and server-side solutions for identity resolution. These tools let you gather, manage, and distribute data seamlessly, filling in the gaps left by third-party cookies. Think of them as the engine that powers your entire data ecosystem and drives your data governance strategies.

Throughout this post, we’ve emphasized the importance of compliant, privacy-focused data practices. CDIs and server-side tag managers make sure that you’re not just following regulations but have a flexible system that’s ready to adapt as privacy laws evolve. They’re designed to future-proof your workflows and tech stack, helping you stay ahead of the curve.

But the real value isn’t just in collecting data—it’s in putting that data to work. CDIs enable you to distribute data in real time, powering personalized marketing, advanced analytics, and coordinated efforts between your sales and marketing teams. In a cookie-less world, the long-term power of first-party data and identity resolution lies in independence. It’s your data, and it allows you to take control, using insights to fuel business growth on your own terms.