After Car2Go eased its background checks, 75 of its vehicles were stolen in one day.

Gephi

Gephi - The Open Graph Viz Platform

MIDAS: Detecting Microcluster Anomalies in Edge Streams

Anomaly Detection on Dynamic (time-evolving) Graphs in Real-time and Streaming manner. Detecting intrusions (DoS and DDoS attacks), frauds, fake rating anomalies.

Investigation into the Unusual Signups

A really detailed analysis of suspicious contributor signups on OpenStreetMap. This beautiful and high-level report demonstrating an orchestrated and directed campaign might serve as a template for fraud reports