Ad Fraud.

Ad fraud is the deliberate manipulation of digital advertising metrics — impressions, clicks, conversions, video views — to misappropriate advertising spend. It encompasses bot traffic (automated programs simulating human browsing), domain spoofing (fraudulent sites masquerading as premium publishers), click fraud (artificially inflating click counts), and ad stacking (hiding multiple ads behind one visible ad unit).

Scale of the Problem

The Association of National Advertisers (ANA) estimates ad fraud costs global advertisers $72 billion annually. Invalid traffic (IVT) rates on open programmatic exchanges can reach 20-40% without active filtering. Brand advertising, video, and mobile are the highest-fraud environments.

Types of Invalid Traffic

General IVT (GIVT) is detectable by standard industry filtering: known data centre traffic, crawlers, and bots identified on blocklists. Sophisticated IVT (SIVT) is harder to detect: human-operated botnets with real residential IPs mimicking genuine browsing behaviour, browser farms where real devices are used at scale, and domain spoofing in bid requests.

Fraud Prevention Measures

Prevention strategies include: ads.txt/sellers.json (IAB protocols that authorise which SSPs can sell a publisher's inventory), third-party measurement from IAS, DoubleVerify, or MOAT, private marketplace deals (lower fraud rates than open exchange), frequency caps (fraudulent traffic often has impossibly high impression frequencies), and data centre IP filtering.