If you have been placing ads in your apps, you have already heard about fill rates and how combining ad-networks through a mediation platform can help you optimize for fill rate.
The math is simple, if you have fillrate below 100%, you are leaving money on the table. Ad-networks have a finite number of advertisers so they will eventually run out of ads to show and so combining a few networks makes sense.
Well…. things change quickly in the mobile ecosystem.
Ad-networks outsource demand
In reality, the situation is a bit different. Most ad-networks have a finite number of direct advertisers but they also make their supply available to other networks. In other words, the ad-network will respond to ad request with their own ads as long as they have them but when they run out they will simply ask other ad-networks if they have ads. If other ad-networks have ads, they will show ads from those networks. This means that the fillrate will be high even for a single ad-network. However, these has some noticable downsides.
eCPM drops when outsourcing demand
What happens when ad-networks are taking ads from other networks? Simple – they are adding more middle mens and more mouths to feed. Let’s say that today you are getting 50% of what the advertiser pays – this is a common situation even if the quoted rev-share is 70% due to ad-network deductions – the standard rev-share only applies when there is one ad-network in the middle. If the ad-network is outsourcing their demand, it means that there are multiple parties that take a share in the middle. If there are 3 hops for example, the publisher will end up getting 12.5% (50% x 50% x 50%) from what the advertiser originally paid.
Adapting to the new situation
It’s pretty hard to tell when an ad-network runs out and starts out-sourcing. However, what you can do is enforce minimal eCPM floors on all networks that you are integrating through your mediation platform. If you enforce an eCPM floor of $1 for rewarded video in US for example, you will start noticing that your fill rate is not 100% anymore on every ad-network. Play around a bit with the threshold to find the right minimum. This will allow you to limit ad-networks to direct relationships. You will also have an indication when they run out – you will see the fill rate gows down. If that happens, this means you need to integrate more ad partners to increase demand. However, you will be integrating them as direct sources and not through a middle man.
Actively tracking your eCPM decay allows you to spot the drops in eCPM that indicates the ad-network is introducing another hop. Check out SOOMLA Traceback to get a grip on your eCPM decay