Detecting Fraud In Tail Spend Using AI Graph Analysis

Detecting Fraud In Tail Spend Using AI Graph Analysis

Tail spend has long been procurement’s blind spot, fragmented, low-value, and often unmanaged. But buried within those thousands of transactions can lie patterns of fraud that traditional audits rarely catch. AI-powered graph analysis is changing that. By mapping relationships between suppliers, bank accounts, purchase orders, and buyers, these systems are surfacing collusion rings and duplicate vendors that would otherwise evade detection.

What’s emerging is a new layer of procurement intelligence, one focused less on contract value and more on network behavior. As companies digitize more of the procure-to-pay lifecycle, the ability to visualize and interrogate transactional patterns is becoming a critical control function.

From Line Items to Relationship Maps

Most ERP systems aren’t designed to detect fraud, they’re designed to process invoices. That leaves procurement reliant on static general ledger checks or retrospective audits that miss subtle red flags: slightly different vendor names with overlapping addresses, POs routed to inactive business units, or repeated micro-purchases just below approval thresholds.

Graph analytics flips the model. Instead of treating each transaction as isolated, it constructs a web of connections, identifying entities that share tax IDs, delivery locations, bank accounts, or purchasing approvers. Vendors that seem unrelated on paper are now being flagged when their behavioral fingerprints match.

Linkurious, for instance, has tracked procurement fraud schemes involving shell companies and collusive bidding across manufacturing and public-sector procurements in Asia, flagging shared addresses, duplicate invoices, and unfamiliar subcontracting behaviors.

Some organizations are layering natural-language processing (NLP) atop this, a dual-threat strategy.  In São Paulo, authorities used NLP to analyze 10,000 invoices, identifying high-priced line items masked by vague or euphemistic descriptions in municipalities’ service contracts. Combining this with graph-driven supplier profiling helps uncover round‑trips, inflated pricing, and shell‑company feeds.

Reclaiming Control Over Tail Risk

Relational Pattern Detection: Map entities across master data and transaction histories to detect suspicious linkages, e.g., vendors that use different names but share logistics addresses or bank details. These connections are often manually masked but algorithmically evident.

Threshold Exploitation Monitoring: Flag repeated purchases just below delegated approval limits, particularly when they occur across multiple departments or over short intervals. These patterns often reveal attempts to bypass internal controls.

Benford and Behavioral Testing: Combine statistical anomaly detection (like Benford’s Law) with behavioral baselines to flag transactions that fall outside historical norms, such as spikes in services spend at quarter-end or sudden vendor additions after budget reallocations.

False Vendor Elimination: Use AI-assisted reconciliation to cross-validate vendors against external databases, corporate registries, blacklists, and sanctioned entity lists, to remove or block fraudulent entries at the source.

Audit Loop Automation: Integrate fraud detection insights directly into sourcing and AP workflows, so that flagged entities are paused, investigated, or reclassified before further spend accrues. This creates a closed-loop feedback system, not just a forensic report.

From Forensics to Prevention

The shift toward AI-driven fraud detection in procurement is not just about post-fact audits. it’s about real-time control. With regulators intensifying scrutiny over procurement integrity, especially in public companies and ESG-sensitive sectors, the ability to identify and act on fraud patterns is now a board-level concern.

The most advanced teams aren’t just reacting to fraud, they’re modeling its likely emergence. By layering AI on top of transactional data, procurement is beginning to serve not only as a cost gatekeeper but as an internal risk radar. And in the murky waters of tail spend, that visibility could be worth millions.

Blueprints

Newsletter