SSP Supply Side Platform

An SSP (Supply-Side Platform) is ad tech software that publishers use to manage digital ad inventory (impressions on websites, apps, or videos), connect to ad exchanges and bidders, and sell that inventory in real-time programmatic auctions (RTB—Real-Time Bidding). Publishers use SSPs to maximize ad revenue by offering inventory to multiple bidders simultaneously, enabling competitive pricing. SSPs aggregate demand from DSPs (Demand-Side Platforms), networks, and direct advertisers, then route winning bids back to the publisher's ad server for display. Google Ad Manager is the market leader; others include Prebid (open-source header bidding solution), OpenX, and Rubicon Project. SSPs handle ad formats (display banners, video, native), audience segments, viewability verification, and fraud prevention.