Companies that provide services to merchants are among the most vulnerable.

The credit card industry processes $US4 trillion in transactions in the U.S. alone.

The credit card processed $US4 trillion in value in the U.S. alone in 2013

The credit card industry is on the brink of a major shake-up.

The credit card industry process $US4 trillion in transactions in the U.S. alone, so it's no surprise startups are trying to shake things up.

Payments startups enter a massive industry that's deeply entrenched.

The credit card industry will process about $US4 trillion in transactions in the U.S. this year.

Credit card-processing is a big target for payment startups.

Credit card processing is a massive industry, with many moving parts. Some are changing fast.

Bitcoin has a number of advantages over the legacy payments system.

The potential for a double-spend attack poses another security issue for Bitcoin.

Investments in new payments startups are helping big payments companies provide better merchants services.

Payments startups enter a massive industry that's deeply entrenched.

Payments consolidation in Europe.