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In late March, a payments processor called Global Payments experienced an enormous security breach, and 1.5 million credit and debit cards from Visa and MasterCard were compromised in the process. As a consumer, you might find this at least a little bewildering. Your bank's name is on the card. Visa or MasterCard's logo is on it. Who, exactly, is Global Payments, and why did they get to build the sloppy security protocols that led to your data being compromised?

It's not a bad question. You enter into a cardholder's agreement with Visa or MasterCard, mediated by your bank. The company processing your payments is determined by where you choose to swipe your card. Merchants sign up with payments processors -- you don't.

So your financial information's security is in the hands of corporations that you don't know the first thing about. Global Payments accounts for a small minority of the payments-processing space, but it compromised more than a million accounts. Doesn't it make you wonder what other companies you've never heard of routinely handle your sensitive financial information?

What do you even know about these companies? Do you want them to handle your info? And do you have any choice? The short answer to the second question is no -- short of hopping off the grid entirely. And you don't want that. What would come of that Klout score you've been working so hard to improve?

1. First Data

Because payments processors are so top-of-mind lately, it would only be right that we start with First Data, perhaps the biggest payments processor you've (maybe) never heard of. This Atlanta-based, 24,000-employee behemoth processes an estimated 60 billion transactions a year, totaling $1.4 trillion in volume. It operates in 34 countries.

Perhaps you've noticed the Star Network logo at your supermarket's checkout aisle and didn't know what it meant. That's First Data's debit payments processing network. This is First Data's only real hint to the public that it exists. Indeed, it isn't even publicly traded despite being so large. KKR, the private equity giant, bought the payments processor in a leveraged buyout in 2007.

Were First Data to experience a security breach on par with what Global Payments did, it would likely be even more damaging to the credit and debit card industry as a whole. Do what you want to keep yourself safe -- don't use your card online, never use it at Bulgarian restaurants, whatever -- but swiping your card at any business puts your information into its system. And those systems can be compromised, as we see again and again.

2. FiServ

Just what FiServ does to make money isn't immediately apparent, but whatever it does, it does it well: It has 20,000 employees and 16,000 clients. The Wisconsin-based company has been in business since 1984, and brought in $4.3 billion in revenue in 2011. FiServ says it "helps (its) clients solve complex business challenges."

What that translates to is payments processing, like First Data, and core banking -- helping banks manage account transactions across multiple platforms. FiServ moved $1 trillion around last year alone -- that's roughly 1/15th of the U.S. gross domestic product. It processed more than 4 billion mobile deposits last year. It's huge and it's everywhere: Last year, it won an award for its core banking solutions in China, from The Asian Banker.

It's the biggest FinTech company out there, and you probably interact with it hundreds of times a year. You just don't know it, and FiServ doesn't stand to gain anything from you knowing more about what it does. What does FiServ do? FiServ provides solutions. What sort of solutions? Business solutions -- don't worry about it.

This question-begging logic extends even to its address, which has a (presumably intentional) internal rhyme scheme -- 225 Fiserv Drive.

3. ChexSystems

While the credit-ratings agencies that determine your creditworthiness are likely well known to most Americans, ChexSystems, the company that essentially does for checking accounts what FICO does for credit cards, remains relatively unknown. ChexSystems keeps tabs on any missteps in your checking history -- problems with overdrafts or bounced checks, for example. And when you want to open a new account, the bank will take a quick look at your ChexSystems record to see if you've behaved well. ChexSystems' report will help your bank decide whether to accept or decline your business. If you're blacklisted, about four in five U.S. banks will deny you a checking account.

Blacklisting can happen to otherwise-responsible customers who have made simple errors. In 2005, a Consumer Affairs story documented how ChexSystems' domination of this part of the checking industry leads to poor consumer outcomes. It told the story, briefly, of a woman who moved to a new town and forgot to cancel her gym membership, which led to her overdrawing her account, and she was unable to open a new account, anywhere.

What's more, ChexSystems' opacity is one of its most frustrating features. Consumer Affairs compared the difficulty of researching the company to "oil-wrestling a contortionist in a frictionless body stocking."

But with so many Americans being pushed out of traditional checking, either because of fees or bad checking histories history, it's worth wondering how fair ChexSystems' nearly monopolistic control over this data really is. Say what you will about credit ratings agencies, at least there's more than one.

Not all banks use ChexSystems, however, and you can find a list of the ones that don't here, at PassChecking. Furthermore, some banks offer "second chance" checking accounts, which can help repair your relationship with a bank, regardless of your ChexSystems record.

4. Yodlee

It's odd to think that a third-party personal finance manager that mediates your interactions with your bank might require yet another party to help it work things out, but that's more or less the case with Before rival Intuit bought, it was powered by Yodlee, a data company that helps power personal finance managers with its account-aggregation software. Today, Yodlee powers Manilla, BillShrink and others.

Yodlee is based in Redwood City, Calif., and it also has offices in London and Bangalore, India. It offers personal financial management and online payment technology services for banks, and -- in the case of -- offers these services to people who offer these services, too. The same is the case with SpringCoin, the debt-management personal finance manager that launched recently.

But it's not all startups for Yodlee. Bank of America announced a partnership with Yodlee last fall, to improve its online banking services. Citibank's Citi Financial Tools is powered by Yodlee. PNC Bank uses Yodlee, too.

This company has been around for just over a decade, and it's helping banks navigate the relatively uncharted territory of online personal finance management. It's likely safer than most everything else on this list, simply because it doesn't process transactions -- yet. But privacy concerns are real -- the reason these personal finance managers exist is, in part, to sell more financial products. They mine your information to find out what you might need most. Helpful or invasive -- you be the judge. Just know that it might not have been designed by your bank.

5. Andera

If you've ever opened a checking account online, you may have dealt with Andera, the self-styled "pioneers of online account opening." More than 500 banks and credit unions use Andera's account-opening services for their websites. Among them are some massive credit unions, including Alliant, and large corporate credit unions for Tyco, General Mills and American Airlines.

And you'd better believe that when you open a checking account online Andera contacts ChexSystems. According to Andera's Partners page: "Andera integrates the ChexSystems and QualiFile solutions with Andera's proven online account opening solutions, to help you turn away risky applicants and avoid incidences of fraud, while retaining your profitable customers."

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See, you can have your application to open a checking account with a credit union or bank rejected without ever really dealing with anyone directly, so long as you do so online. Isn't technology incredible?

In conclusion

We're realistic here; we understand that technology advances at a clip that banks couldn't reasonably hope to keep up with. And, banks, when they were created, weren't supposed to be involved in all of our cash transactions -- that's a product of technological advances, too. So it makes sense that banks lean on those with more knowledge about all things high-tech. But even a company that is a leader in technology isn't necessarily infallible. As we rely more and more on devices and software to make our money go to the people and companies we want it to (or need it to), more and more startups and faceless corporations will get in the game.

Regardless of how we feel about the big banks, at least they've been around the block. The banks are publicly traded and subject to regulations. They have press contacts and are covered by countless publications. Even if it's just faux-transparency, these institutions have to answer to shareholders, regulators, customers and journalists (sort of). When they farm services out to third parties, the chain of culpability and accountability is somewhat broken, or it's obfuscated. And that is at least a little worrisome.

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