MarTech Landscape: What is a supply-side platform (SSP)?

Supply-side platforms  (SSPs) help publishers sell digital ad impressions in automated auctions. Publishers can sell and manage display, video or native ad inventory on desktop and mobile through SSPs. In this installment of Marketing Land’s MarTech Landscape Series, we aim to chop through the jargon and explain what supply-side platforms do, how they work and why they matter.

What do sell-side platforms do?

Supply-side platforms — also called sell-side platforms or yield optimization platforms — are used by digital publishers to manage the sale and fulfillment of their advertising “supply” and ultimately, get the highest prices for their ads.

SSPs are software platforms that function similarly to their counterpart, the demand-side platforms (DSPs) advertisers use to buy digital advertising programmatically. However, SSPs are designed specifically to help publishers sell ad impressions — mobile, video, display and so on — at maximum CPMs (cost-per-thousand impressions).

How do SSPs help publishers get the best CPMs?

Through a supply-side platform, publishers can open up their advertising inventory for bidding to many ad buyers on various ad exchanges, ad networks and demand-side platforms. The idea is that by putting available ad impressions in an auction that can attract a large number of buyers, the increased demand will drive up bids and yield higher CPMs.

The automation enabled by SSPs provides efficiencies in two ways. SSPs enable publishers to automate and speed up the traditional back-and-forth negotiations between ad sales and media buying teams. They also allow publishers to leverage vasts amounts of data in ways that aren’t feasible in a manual buying process.

How do SSPs use data?

In addition to helping publishers reach a wider net of potential buyers, SSPs enable publishers to share the valuable data they have about their users at the ad impression level. When publishers make unsold ad impressions available through an SSP, the buyers — DSPs, ad exchanges and ad networks — will take into account the content of the page where the available ad impression appears, as well as the user data the publisher has for that impression (data might include demographics, location, browsing and purchase history) and match it against the audience targeting criteria set by the buyers. If the publisher data and advertiser targets overlap, the buying platforms will bid on the ad impression in an auction (often held in real time at the instant the impression becomes available) on behalf of the advertiser. The winning bid gets the impression.

Are SSPs similar to ad exchanges?

As SSPs have attracted a critical mass of publishers selling and managing inventory through their platforms, the SSPs have come to act like ad exchanges, and many have launched ad exchanges. Just as with a typical ad exchange, buyers can access inventory programmatically across a number of publishers selling via an SSP.

Even as the lines have grown fuzzy, there are a number of capabilities that SSPs are designed to handle. For one, SSPs can connect to mulitiple ad exchanges, ad networks and DSPs. SSPs also give publishers controls like the ability to set minimum bids, or pricing floors, on certain inventory and make certain inventory available only to specific buyers, exchanges and networks.

What are some of the major SSPs?

ONE by AOL for Publishers, AppNexus Publisher Suite, DoubleClick for Publishers, OpenX, PubMatic, Rubicon Project, Yahoo-owned BrightRoll and Facebook-owned LiveRail are among the biggest supply-side platforms.