What Is SSP Log Level Data? And How You Can Use It?

Updated on: February 22, 2024
SSP log-level data brings more transparency and help you to optimize the ad inventory based on how buyers are bidding. Wondering how? We got you covered.


Publishers and advertisers are always looking for new and improved ways to measure media and ad campaigns. And no doubt, they have come a long way in terms of the capabilities of their analytics tools. But with all of these capabilities, there is something getting lost in the shuffle: transparency.

IAS’ recently published ‘Industry Pulse Report 2021’, 36% of respondents said accurate measurement remains their top industry challenge, whereas 34% of respondents said the assessment of campaign ROI is the biggest challenge for them. The two challenges, in particular, show us how agencies and advertisers approach transparency.

This trend isn’t anything new, and it’s largely due to the increased number of middlemen, a shift to first-party auction, ad fraud, and dominance of walled gardens. Being said that, SSPs have started bringing more visibility and transparency to the auction environment by providing log-level data.

What Is Log-level Data?

Log-level data is a set of attributes that are relevant to a single ad impression. We’ve talked about the basics in this article. When we talk about SSP log-level data, the main types of data that advertisers look for are transactional data that gives insights into how an auction operated and how much fees they are being charged with.

Advertisers can get insights into auction dynamics and identify the missed opportunities and how a fair price reaches that impression. With log-level data, advertisers can be better informed on media planning and buying and improve their ROI. By using log-level data, advertisers can be better informed on media planning and buying and improve their ROI.

“Asking for log-level data started as an auditing mechanism, and it has evolved into a bidding strategy facilitator.”

– Amanda Martin, VP of Enterprise Partnerships, Goodway Group (Src

Does that mean SSP log-level data is beneficial for the buyer-side only? Of course not. It is equally helpful for publishers. Let’s understand how.

Why Does SSP Log-Level Data Matter?

For Publishers

Since publishers are the ones who are directly connected to the supply side platforms, log-level data enables them to optimize their ad inventory performance. To put it simply, publishers can evaluate how buyers are bidding for their ad impressions over time. 

This raw data not only gives a complete picture of buyers’ performance but also provides insights into traffic strategies and user information (non-PII). We’ll see later what kind of log-level data you can get from an SSP. In a nutshell, SSP log-level data allows publishers to:

  1. Better optimize the floor prices.
  2. Improve their ad fill rate.
  3. Come up with better selling strategies.
  4. Improve the relevancy of ads served on the website.
  5. Improve ad revenue.

For Advertisers

The programmatic supply and demand chain is not straightforward in nature. There are a number of intermediaries at each level of the process. These intermediaries can have varying grab rates, publisher relationships, and so on — and that’s why advertisers need Supply Side Platforms log-level data. To optimize the supply chain, measure the ad campaigns accurately, reduce the discrepancy between ad servers and DSPs.

In a nutshell, it allows advertisers to:

  1. Enhance their ROI.
  2. Come up with better buying strategies.
  3. Protect their brand from serving ads on low-quality websites.
  4. Reduce ad-tech tax.
  5. Improve customer experience and journey.

What is the Important Information in SSP Log-level Data?

When it comes to the log-level data that SSPs should provide, there are three categories of information that are vital:

  1. Bidding specifics
  2. Auction dynamic specifics
  3. Insights into inventory

Bidding Specific Data Points

Various anonymized information on bid price can tell you about:

  1. Auction Clearing Price,
  2. Bid Price of Inventory,
  3. Highest Bid Price,
  4. Second Highest Bid Price,
  5. Floor Price,
  6. Ad Fill Rate,
  7. Loss Reason (relevant for advertisers), and more.

Auction Dynamics Data Points

  1. Exchange implementation type (confirm tactics such as waterfall and header bidding, relevant for advertisers),
  2. Seat ID,
  3. Deal ID (relevant for advertisers), and more.

Inventory Verification Data Points

Ads.txt (informs whether the publisher has authorized sellers or not, relevant for advertisers).

Note: We’ve listed a few data points that are included in log-level data and are often used by publishers and advertisers. However, log-level data consists of a pool of raw data, and it depends on the SSPs to give you access to a certain amount of data.

Undeniably, the combination of various data points improves the transparency of ad selling and buying. But then there’s a catch.

Why Isn’t Everyone Using SSP Log-Level Data?

First, as we said earlier, log-level reports consist of terabytes of raw data. Hence, it requires a data analyst/scientist to understand the data and create meaningful reports.

“Event-level data is enormous, from a volume and breadth standpoint. The potential use cases for the recipient can be limitless, but there is also a considerable investment required to produce, store and analyze the data.”

– Joey Leichman, VP of Buyer Development, OpenX (Src

Due to this challenge, there are only a handful of publishers like The Guardian and advertisers like Nestle and L’Oréal leverage log-level data. Second, not all SSPs provide log-level data for free on request. While some SSPs ask for a monthly fee to give access to log-level reports, others agree to share hardly 1% of log-level data with the publishers. 

Third, there’s no standardized format for sharing log-level data. While most SSPs don’t reveal publisher’s data to the full extent, DSPs restrict the information they share with the advertisers.

“If the ad tech industry wants log-files to be useful for brands then we need to have standards for how they’re reported. Without standardization, log-files aren’t a workable way to get transparency into the supply chain because of how many there are.”

– Tom Kershaw, Chief Technology Officer, Rubicon Project (Src)

Do you Need SSP Log-Level Data?

It varies from publisher to publisher. The Guardian has been leveraging log-level data for five years. The publisher has taken ownership of its data in order to reduce the ad-tech vendor fees in the open exchanges and improve the transparency for its advertisers. As a result, the programmatic ad revenue had increased by 40% Y-o-Y, according to the publisher.

So, if you’re serving hundreds of millions of ad impressions every month, and have enough in-house resources to decode the data, you can ask for log-level data from your SSP.

“That’s a very positive step. Any extra cash that goes directly to news media organizations will fuel the great content that users really want to engage with, which is positive for the wider industry as a whole.”

 – Jason Jutla, Head of Media Activation for Essence (Src)

What’s Next?

The fight for transparency in the programmatic industry is not new, but it is heating up. And as advertisers become more educated about the inner workings of their programmatic media buys and DSP technology, they’re turning to SSPs and publishers requesting log-level data about the bids they’ve won or lost. So, if your buyers are looking for the same, reach out to your SSP or ad exchange.

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