Supply path leakage. How to use FouAnalytics to reduce this leakage

Already use inclusion lists? Great. But are you sure your ads are going to the sites and apps in your inclusion list? If you're relying on the placement reports of the DSP or ad server you are using, you may not be getting the full picture. Why? Both the DSP and the ad server records the domain passed in the bid request, not the domain on which the ad was actually shown. That means, if a fake site (fakesite123 .com) lied about the domain in the bid request and put espn .com so they can get bids, espn would be reported to you in the placement reports and log level data. You won't see fakesite123 in the placement reports. The same goes for MFA sites that all started mis-declaring the domain in the bid request to get around "MFA block lists" purchased from adtech vendors.

FouAnalytics does not sell "MFA block lists" or block lists of bad sites and apps, because you don't need them. Instead, you need postbid javascript detection to DETECT where your ad actually went. Then, if those sites and apps DON'T match what you have in your inclusion lists, you know there's a problem that needs to be fixed. Let me explain how you can see these problems by using FouAnalytics, that you can't see in placement reports or log level data.

Supply path leakage - i.e. your ads NOT going where you want

Let me illustrate what "supply path leakage" means. When I tried to target a single domain using an inclusion list of just 1 domain, only 73% of my ads went to that domain. A quarter of my ads didn't go where I wanted them to go. In this first scenario, I did not specify which exchanges (so all remained active, which is the default). When I eliminated all but one exchange, the accuracy went up to 97% -- i.e. 97% of my ads went to the 1 domain I specified in my inclusion list. That "delta" of 24% (from 73% up to 97%) is the supply path leakage -- ads not going to the sites and apps in your inclusion list. Even if you specified the shortest possible inclusion list (1 domain), if there are too many exchanges and combinations of supply paths, your ads may not get to the right place. Imagine if your inclusion list had thousands of sites and apps in it. What percentage of your ads are getting to the right places?

How many exchanges or supply sources are active?

If you have FouAnalytics in-ad tags to track your ads, you will see the following data grids passed by the macros of the DSP -- for example, custom_site, custom_supply, custom_ssp, custom_ADSTXT_AD_SYSTEM_DOMAIN (see screen shot below)

In the leftmost example above, the top 10 supply sources (highest volume first) are listed in the grid. The "25 more" on the bottom right tells you there's 25 more rows that will expand when you click that. That means this campaign has a total of 35 supply sources in use. In the middle example, you see 5 exchanges; but note the top one accounts for 97% of the impressions. And finally, the rightmost example shows the top sources of the ads.

The next set of 3 data grids shows the distribution of ads across exchanges when DV360 is used to buy ads. Note how Google favors its own platform and 78 - 98% of the impressions come from Google supply.

The following 3 data grids show a better distribution of the ads across the top 10 supply sources, not so concentrated in one supply source like Google.

Uncheck as many exchanges as possible

Having dozens of exchanges active in a campaign is the root cause of supply path leakage -- i.e. your ads not going to where you want. Why have you not seen this before? It doesn't show up in placement reports or log level data, because those contain the domain passed in the bid request, not the domain where the ad ended up. With FouAnalytics, you can see this because the domain was detected after the ad was rendered -- i.e. using a postbid javascript tag. If these domains and apps don't match the ones in your inclusion list, you can take action. You can go into your campaign settings and reduce as many supply sources and exchanges as possible by unchecking the checkboxes next to each exchange. For example, you don't need 45 exchanges active. You probably only need 3. How do you choose? You can first eliminate the supply sources/exchanges that have the most dark red (see the color coding under each row).

Furthermore, most sites, especially the fraudulent ones, sell their ads through as many exchanges as they possibly can. The exchanges are also all interoperable, because they don't want to miss out on taking tolls from as many ad opportunities as possible. There are layers and layers of other shady things which I won't get into here. But suffice it to say you will get pretty much all of the sites and apps you want even if you reduce the number of exchanges from 45 to 3. Let me show you some concrete proof here. Taking 2 sites commonly seen in programmatic buys, yahoo.com and msn.com, you will see they each sell through multiple exchanges. In the case of Yahoo (left side), you can see that the top 2 represent 70% of the volume. In the case of MSN (right side), you can see that the top 4 exchanges represent 99% of the volume. Those are the exchanges you leave ON, and turn off the other 30 because they are not needed, i.e. redundant.

By turning off as many exchanges as possible, you also reduce the supply path leakage and increase the accuracy of your ads going to the sites and apps in your inclusion list.

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