The Hidden World of Advanced Third-Party Data: A Balancing Act Between Privacy and Precision
Friday September 19, 2025
In the digital advertising world, there’s what you see…and then there’s what’s really going on. Ask most marketers about audience/demographic targeting, and you’ll hear the usual suspects: age, gender, location, and interests
These are the safe, surface-level attributes everyone talks about; the ones that sound harmless at a conference or in a client meeting. But in reality, there’s a deep, largely invisible layer of data that is quietly fueling some of the most precise, and arguably intrusive, ad targeting in existence.
The Scary World of Advanced Data?
Third-party data providers - data brokers, analytics giants, and niche aggregators - collect and have access to a staggering amount of information about individual people. This isn’t just the standard stuff scraped from your social profiles.
I stumbled upon this world over eight years ago while doing research for a client. What I found shocked me.
There are a handful of large data aggregators out there and hundreds of resellers that acquire your information. It’s stitched together from data points like:
• Credit card purchase records (aggregated at scale)
• In-store foot traffic data from mobile GPS pings
• Home ownership details and estimated property values
• Household composition — including the number of children and their likely ages
• Media consumption patterns — including not only what people watch or read, but also when and how often
• Life events like engagements, divorces, relocations, or a new baby in the home
• Propensity models that predict how likely you are to buy specific products within a set timeframe
This isn’t the kind of data you can “select” from a simple drop-down menu in Facebook Ads Manager.
It’s buried in specialized datasets, quietly licensed between platforms, and often blended into algorithmic “audience segments” so advertisers never see the raw details.
If this sounds concerning, that’s because it is. I often tell clients about this level of detailed information I can get on a person (or a competitor) and they are stunned, and almost always terrified.
The Widening Scope of What’s Available
It’s one thing for an advertiser to know you’re interested in travel because you follow a travel influencer. But it's another level for them to know you’ve been to an airport twice this month, your average hotel booking spend, and that you recently browsed luggage online but didn’t purchase.
And that’s just the beginning.
Here are just a few examples of data I can collect on YOU right now:
• If you contributed to a Republican or Democratic candidate or campaign
• How many kids you have, their ages, and if they live with you full-time or part-time
• Credit Score (although technically, due to legal purposes, this is a representation of your ‘credit worthiness’ and not your actual “credit score”)
• Your estimated Income and/or total Household Income
• What kind of car you own, how old it is, and how much you owe on it
• What medications you are currently in the market for and things like if you’ve been to a doctor in the last couple years and for what. Here is an actual description of one of the targeting options: Women over the age of 50 who are likely to have had a breast exam within the past 5 years.
• Your phone’s SFID or MAID (basically your phone’s fingerprint)
• Your home IP address of your WiFi, Siri, Google Assistant or Alexa
• We can even trigger advertising based on keywords you’ve said to your Alexa or Google device recently. Yes…we’re listening as well
But the real question is: what’s the reason for all this? And is there a benefit?
Why It Matters
The short answer is yes. We know this data seems intrusive, and all-encompassing, but it doesn’t have to be scary. Savvy advertisers are combining data with creative targeting to deliver messaging that is effective.
Ask yourself this: how many times have I seen or heard an ad that was absolutely useless to me?
The answer is probably hundreds. And the reality is, that it’s probably even more than that!
Consumers today are bombarded with literally thousands of messages daily. Advanced data collection and targeting can help advertisers make more informed decisions that can cut down on that noise.
When used responsibly, data transforms advertising from an intrusion into a service that adds value for both advertisers and the consumers. But responsibility is a keyword here.
A Balancing Act for Advertisers & Audiences
Again, data seems intrusive because of the remarkable level of detail that’s collected. And, for this reason (and others), most third-party data aggregators want to stay hidden. Many consumers have no idea that their purchase decisions and offline actions are being captured, packaged, and sold in the background. And although we all passively sign off on terms & conditions, being tracked with such precision can still feel like a breach of privacy and trust.
Over the years, though, many tech giants and regulatory agencies have stepped in to protect consumer privacy and make sure there’s a standard code of conduct.
So, as responsible advertisers and informed consumers, there’s a balancing act we should honor.
For advertisers:
• Understand what’s truly possible, but weigh it against the risk to trust and brand reputation.
• Ensure every data source you use is privacy-compliant and ethically-sourced.
• Remember, transparency is a competitive advantage. The brands that explain how and why they target often earn more loyalty.
For consumers:
• Be aware that online tracking goes far beyond cookies.
• Utilize tools like privacy settings, VPNs, and tracking opt-outs. These won’t make you invisible, but they can limit the data flow.
• Identify your boundaries and know what’s possible. The more you understand how advertising works, the more power you have in managing your experience.
Final Thought
The abundance of advanced third-party data is both a marketer’s dream and a privacy advocate’s nightmare. The question isn’t whether this data exists — it’s whether we’ll use it responsibly, or keep pretending it’s not there. But, in today’s landscape, there’s no going back. That is, unless you want to go back to your 2004 Motorola RAZR! And even then, there’s no guarantee we’re not watching!