Viant Technology operates a demand-side platform (DSP) that lets advertisers and agencies programmatically buy digital advertising across connected TV (CTV), streaming audio, digital out-of-home, mobile, and desktop through a single self-service interface. Viant makes money by charging advertisers a fee — either a percentage of spend or a fixed CPM — on ad spend transacted through the platform. The key economic metric is contribution ex-TAC, which represents revenue net of the cost of purchasing ad inventory, reflecting Viant's actual take from the platform. CTV is the largest channel, accounting for roughly 45-46% of platform ad spend. Viant's core differentiators include its patented Household ID (HHID), which links digital identifiers to roughly 125M U.S. households and works in cookieless environments like CTV; IRIS_ID, a content identifier acquired with IRIS.TV that enables scene-level contextual targeting in CTV; and Direct Access, a supply path optimization program that connects advertisers directly to premium CTV publishers like Disney, Paramount, and Roku, bypassing middlemen. Viant also offers ViantAI, an AI suite covering bid automation, media planning, measurement, and fully autonomous campaign management. Viant's customers are primarily U.S. advertising agencies and mid-market national brand advertisers. The business model benefits from operating leverage, as the self-service and AI-automated platform allows ad spend to scale with minimal headcount growth. Viant positions itself as the only fully independent, buy-side-only enterprise DSP, arguing competitors like Google, Amazon, and The Trade Desk are conflicted by their ownership of ad inventory.