The same primitive — match, enrich, verify — composes into three shapes. Here's each one as a real marketing scenario: who holds what, what crosses the wire, and the question that gets answered without anyone's list ever moving.
A DTC coffee brand and a national magazine want to run a co-branded campaign — but only to people who are already customers of both. Neither will hand over its list.
The setup. Roast Co has 1.2M CRM emails. The Atlas (a publisher) has 4M subscriber emails. They want the size of the overlap, and the ability to target it — without Roast Co learning The Atlas's subscriber list, or vice versa, and without either uploading to a third party.
T = HMAC(k, email) on Roast Co's own infrastructure.311,402 shared customers.One data provider publishes a queryable signal; thousands of marketers enrich their own audiences against it — each seeing only answers about records they already hold.
The setup. SignalIQ maintains an IP → buying-intent dataset (e.g. in-market: auto-insurance). Hundreds of agencies and in-house marketing teams want to score the traffic and email lists they already have. SignalIQ wants to monetize per-query without shipping its whole dataset to anyone, and the marketers don't want to reveal which visitors or customers they're scoring.
$0.002/query) and rate limits.Independent retailers pool a high-value-shopper signal into one shared audience — without any retailer exposing its customer list to the others or to the aggregator.
The setup. Four mid-size retailers each know their repeat, high-LTV buyers. None is big enough to interest a national ad platform alone, and none will share its customer file with a competitor. They want a combined “premium shopper” audience an advertiser can target — built so the co-op aggregator never holds anyone's raw list, and no retailer learns another's customers.
| Topology | Marketing example | Who holds data | What the asker learns | Where the money is |
|---|---|---|---|---|
| 1 : 1 | Two brands measure & activate audience overlap | Both parties, symmetric | Size of overlap + the matched segment | License / per-deal |
| 1 : many | One provider sells enrichment to many marketers | Provider holds the signal; consumers hold queries | Signal for records it already has | Per-query metering |
| many : 1 | Retailers pool a premium-shopper audience co-op | Many contributors; aggregator holds only tokens | Membership in the combined set | Contribution + usage revenue share |
Start with one vertical and one topology — overlap, enrichment, or a co-op — and prove the no-pool guarantee on your own data.