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Fraud Fundamentals

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Before you pick fraud tools or write rules, understand the concepts that drive every decision in fraud management. These two pages cover the "why" behind fraud strategy.

What You'll Learn​

PageWhat It CoversRead This If...
Economics of FraudThe true cost of fraud (direct losses, false positives, operational costs, customer impact)You need to justify fraud prevention spend or understand why blocking too much is also expensive
Risk AppetiteHow to balance fraud loss tolerance, customer friction, conversion targets, and regulatory requirementsYou're deciding how aggressive your fraud rules should be or where to set your score thresholds

The Core Trade-off​

Every fraud decision involves the same trade-off: block more fraud vs. block fewer good customers. Tighten your rules and you catch more fraud but reject more legitimate sales. Loosen them and you approve more revenue but accept more losses.

The right balance depends on your business. A $5 digital good has different economics than a $500 physical product. A business at 0.1% fraud rate makes different choices than one at 1.5%.

These two pages give you the framework to find your balance:

  1. Start with Economics to understand what fraud actually costs (it's more than just the transaction amount)
  2. Then read Risk Appetite to set your thresholds based on your specific business model

Key Principles​

  1. Not all fraud is created equal – First-party (customer abuse) and third-party fraud (stolen cards) require different responses
  2. Prevention has costs too – False positives hurt revenue and customer relationships (see Economics)
  3. Speed matters – Early detection limits losses; see Detection Framework
  4. Data is your weapon – Invest in device fingerprinting, velocity rules, and evidence collection
  5. 3DS is your friend – 3D Secure shifts liability for stolen card fraud to issuers
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