For most people, PayPal is the dusty old middleman of the internet—just a legacy brand wedged somewhere between your bank and your Venmo pizza split. A fossil from the dot-com days. A digital checkbook. A punchline.

But walk past the fintech façade, peek into the fluorescent-lit labs of San José, and you’ll find something entirely different brewing—a full-blown adtech Frankenstein stitched together by one of the most methodical minds in the business: Dr. Mark Grether.

We spent weeks embedded with the PayPal Ads team. We met with engineers, strategy leads, and Grether himself—who, frankly, gives off the precise energy of a man who once co-founded Xaxis, ran Amazon’s ad strategy, and built Uber Ads into a billion-dollar business. He didn't cackle in German, but he might as well have.

They gave us “the tour.” What they didn’t realize is that we were watching everything. And while they polished their pitch decks for Cannes, we took notes on the reality: PayPal isn’t just building an ad platform.

They’re building a media operating system for money itself.

The centerpiece of this entire experiment? Something they lovingly call the Transaction Graph. Sounds harmless. Clinical. But make no mistake—this is the most commercially potent surveillance map you’ve never consented to.

We saw it in action. It's not just what you bought. It's when, where, with whom, how often, and in what order. And it’s not a guess. It’s not modeled. It’s the real thing: receipts.

Let’s say you used PayPal to buy Nikes on StockX, a plant-based burger at a ghost kitchen via Venmo, and then browsed Sephora with a Honey coupon you forgot you even installed. That triangle of behavior? Mapped. Merged. Monetized.

This isn't a retail media network locked inside a grocery store’s app. This is a real-time, cross-merchant, cross-platform picture of how money moves—across 400 million users and 30 million merchants, across digital and physical, across your lifestyle.

And unlike cookies, this data doesn’t expire. It doesn’t disappear when Apple gives you a warning. It’s tied to actual verified transactions. Try opting out of your own credit card history.

Here’s where Grether’s real genius kicks in. Most companies would kill to launch a new media product. A shiny portal. An attention-grabbing experience.

Grether? He doesn't care about eyeballs. He cares about intent. What Uber gave him—context, frequency, immediacy—PayPal gives him in spades. But horizontally. Across the entire ecosystem.

When asked what he saw in PayPal that others didn’t, he laid it out plainly: “We see 25% of global e-commerce. This isn’t just a platform. It’s a two-sided ecosystem—signal and scale. And that means we can do something no one else can.”

That something is bigger than slapping ads on a checkout page. It’s about becoming the connective tissue between consumers and commerce, not on one site—but across all of them.

Retail media today is a junk drawer of siloed platforms. Kroger does Kroger. Walmart does Walmart. You want to know what happens between them? Good luck with your Frankenstein spreadsheet. But PayPal sees everything between the silos. And that’s exactly the moat.

Here’s the part that honestly shocked us: Venmo is PayPal’s secret weapon.

Most people think of it as a money app with emojis. In reality, it’s a social commerce graph hiding in plain sight.

We dug into the behavioral signals and… it’s gold. People tag transactions with pizza slices, lipstick, gym flexes, and Sephora trips like it’s a diary. And these aren’t vague “likes” or engagement guesses—they’re timestamped purchase intent tied to real money movement.

According to PayPal’s team, 48% of Venmo users are Gen Z or Millennials. Half of them check the app multiple times a week. And many of them do what Grether calls “shadow shopping”—splitting purchases, coordinating group buys, comparing notes publicly.

It’s TikTok for money—but nobody’s noticed.

And yes, if you’re Domino’s, you can now run emoji-based targeting. Not a joke. 🍕 is an actual audience segment.

The real magic trick? PayPal isn’t just buying its own hype. They’re selling access to their data across the open web.

They’ve launched offsite ads—curated PMPs that let advertisers buy PayPal-powered audiences in other ecosystems. Grether made it clear: they’re DSP-agnostic. They don’t care what pipe you use. As long as you buy into the transaction graph, they’ll let you tap the signal.

Want to target people who bought skis in the last 60 days? People who share pizza every Friday? Parents who split beauty products on Saturdays and order Chipotle on Sundays? That’s not targeting. That’s predictive shopping logic, and PayPal is quietly handing it out to the buyers who know what to ask for.

What Facebook used to do with browsing history, PayPal is doing with actual wallets. The difference? One made you paranoid. The other makes you a better marketer.

Grether thinks so. He’s already done it once at Uber. At Amazon, he helped engineer a machine built on first-party dominance. But this? This is bigger. Because the pitch isn’t just adtech.

The pitch is "we know what consumers do when they spend real money.” Not what they search. Not what they scroll. What they swipe.

There are risks, of course. Consumers are touchy about privacy. The term "data" is radioactive. But PayPal’s secret weapon is trust. They’re not Meta. They’re not scraping browser tabs or harvesting messages.

They’re just doing what you asked: keeping a record of what you paid for—and making that record useful.

Whether that translates into a revenue engine big enough to rival the walled gardens? We’ll see. But from what we’ve seen behind the curtain, they’re not just building a media business. They’re building a new layer of the economy.

We pulled back the curtain on PayPal’s plan to turn 225 billion transactions into the most precise advertising engine on the internet—far beyond anything a traditional retail media network can offer. Inside ADOTAT+, you’ll find the full story: how Hugo Boss and Verizon are using PayPal’s transaction graph to measure market share in real time, not just conversions; how cross-merchant attribution is finally solving the “where did my customer go” problem; and why CFOs are now watching media plans like P&Ls.

You’ll also see why Venmo is quietly becoming the most underpriced attention market in commerce. We mapped how PayPal Ads is using pizza emojis, beauty splits, and payment memos to target moments, not demographics—and why it might raise more legal eyebrows than Meta ever did. If you want to understand the ad platform that’s built on trust, not clicks—this is where it starts. Unlock it in ADOTAT+.