DEFINITION
Bid Rigging
Bid rigging is the manipulation of a competitive procurement process so that the outcome is predetermined. Bidders coordinate rather than compete, through mechanisms such as cover bidding, bid rotation, market allocation, or bid suppression.
The defining characteristic is that apparent competition is structural rather than real. Detection therefore tests whether bidders are genuinely independent: shared bank accounts, tax identifiers, addresses, phone numbers, or directors across bidders are direct evidence of connection.
Where bidders deliberately share no attributes, behavioural indicators take over — win rotation across a stable bidder set, consistent bid spreads, correlated pricing, and repeated joint participation. Graph analysis then tests whether the bidders connect through any intermediate entity.