By Kasey Byrne

Today?s marketers want access to consumer purchase data ? i.e. the Holy Grail of ad targeting. To obtain it, some are building sophisticated applications and shopping platforms, and expending big ad budgets to get consumers to use them for searching, shopping and transacting.

However, if you flip that thinking on its head and hand control to the customer, you will land in a burgeoning new sector called card-linked marketing.

Right cards
The companies in this space start with consumer purchase data already held by banks, and use it to deliver exactly the right message at the right time, to the right individual.

Card-linked marketers see the world through the lens of individual buyers.

Billions of purchases on banks? debit and credit cards lend insights into the purchase behavior of millions of active buyers.

Using proprietary technology, card-linked marketers target ads to individuals based on their recent purchases, through their online and mobile banking statements. Who is the best target for a product or service? Turns out, an already active buyer in that sector. Targeting that buyer leads to increased engagement and double-digit returns.

Card-linked marketing was literally impossible before now.

The explosive growth of digitized payments ? people paying for things with debit and credit cards instead of cash ? combined with the expanding adoption of online banking has set the stage for a mobile banking and marketing revolution.

Card transactions are now the preferred method of payment among consumers, and this method produces an immense amount of data about their purchase behavior ? data that was not accessible just a decade ago.

Today, card payments make up 66 percent of in-store transactions, and debit card use has grown from 8.3 billion transactions in 2000 to 46.7 billion in 2011 ? an average growth of about 19 percent annually.

Bank on it
With regard to online banking going mobile, 37 percent of today?s app users download mobile banking apps.

By processing the everyday transactions of today?s consumers, banks now have extensive data on the purchasing habits of millions of customers, and a trusted channel of communicating with them ? their online and mobile banking statements.

Moreover, this revolution is consumer driven. Consumers use online and mobile banking just about as much as they do social media.

How are card-linked marketing companies gaining access to purchase data at the banks? By using technology that enables targeting without revealing the personal identifiable information of the consumer.

Card-linked marketers can only see the purchases, not the person. This patented technology is the genesis of this burgeoning sector predicted to be $115 billion by 2015, according to financial research firm Aite Group LLC, and it is giving marketers the rich purchase data for which they long.

Still, some deep-pocketed marketers are investing very real dollars developing their own mobile commerce apps and platforms to capture purchase data.

However, even if this strategy succeeds, they will only have data for the buyers that buy from them, on their platforms. Banks already have that data ? you can ?take it to the bank.?

Pursing data
Purchase data from banks gives advertisers a whole-wallet view, so marketers can see where their best customers are shopping ? when they are not shopping with them. Those insights are revealing big surprises about the profiles and personas that we hold so dear.

So, today?s big retailers and marketers need to decide which road to choose. They can try obtaining purchase data via their own apps and mobile commerce platforms, but their success will be expensive and limited.

These marketers will also have to become very savvy application developers with sizeable budgets dedicated to maintaining those apps and interpreting that data ? while also worrying about keeping their consumers engaged.

The other choice is to flip their thinking and start looking for the best source of purchase data and technology.

CARD-LINKED MARKETING is helping a lot of household names gain measurable increases in sales, by serving ads to active buyers in their category at a scale they are used to seeing in traditional media such as television and direct mail.

All transactions end at the bank.

With cark-linked marketing, retailers and marketers have a new way to get to the Holy Grail of purchase data and see the big returns they knew it would yield right now. Many have already flipped and are enjoying the upside until the secret is out.

Kasey Byrne is senior vice president off marketing at Cardlytics, Atlanta. Reach her at .