One of the main mechanisms that Google Ad Manager uses to decide which ad is served is line item priority. Depending on your account set-up, there are up to nine different ‘type’ options for each line item, ranging from Sponsorship to Click-tracking only. These types determine how each line item is delivered and how it will compete with other line items and yield groups. Like many parts of Ad Manager, line item types and priorities can be confusing at first, but are logical once you understand how each type behaves and how they interact with each other.
Understanding which to use and how these line item types interact is essential to ensuring a smooth running and profitable ad stack.
Each of Ad Manager’s line item types is explained below. Click here if you know what the types mean, but want to skip ahead to how they interact and are affected by dynamic allocation.
Line item types vs priorities
Each line item type also has a priority, as shown in the table below. The type determines how the line will be paced and delivered and priority governs how each line will compete against other eligible line items.
Line types with the lowest have the highest priority when Ad Manager decides which line to serve. It can be useful to think of the number as a ‘weight’ with the ‘heaviest’ items sinking to the bottom. In priority order, the available types are:
Sponsorship (Priority 4)
Sponsorship lines are the top priority, meaning that eligible Sponsorship lines will serve ahead of lines of any other type. Sponsorship lines serve to a set percentage of impressions, so a single line item set to Sponsorship will serve into every impression that is eligible for that line item and no other ads will be shown.
When creating a Sponsorship line item a rate (price) can be set for it either on a CPC – Cost Per Click, CPM – Cost Per thousand impressions or CPD – Cost Per Day basis. This rate doesn’t affect the delivery of the line, just the value of those impressions in reporting.
If two competing Sponsorship lines are created (for example, two lines given a goal of 100% of impressions each), Google Ad Manager will randomise which line is served and attempt to give them an equal share of impressions.
Sponsorship is a Guaranteed line item type, meaning that Ad Manager will attempt to serve every booked impression regardless of whether this is the most profitable approach.
Standard (Priority 6, 8 or 10)
When creating a Standard priority line item you can choose to set the that line to Standard High (priority 6), Standard Normal (Priority 8) or Standard Low (Priority 10). This allows for greater control when prioritising multiple line items that will be served as Standard.
When booking Standard line items you must provide a Quantity, either of Clicks or Impressions. Standard lines are Guaranteed, so Ad Manager will always attempt to deliver the booked quantity. If there are standard lines that are running behind schedule, Ad Manager will serve those lines ahead of any other than Sponsored – even if that is not the most profitable approach.
It is worth noting that when a quantity is promised in Clicks for lines with a lower than expected Click Through Rate, this can result in a great number of impressions being given to a standard line as Ad Manager attempts to meet the delivery goals.
Ad Exchange (Priority 12) and AdSense (Priority 12)
The AdSense and Ad Exchange line item types are identical, but deal with demand from the two respective Google products. Both types are only given as options on accounts that have been enabled for third party services. If you need this option enabled talked to your GCPP or Google account manager if you don’t work with a GCPP.
The Ad Exchange and AdSense line item types allow for AdSense/AdX to be trafficked as line items that use Dynamic Allocation to compete against other remnant (non-guaranteed) line items. This essentially allows the line to compete at the value of the winning AdSense/Ad Exchange bid for each impression. This is the preferred way to serve either AdSense or Ad Exchange through Google Ad Manager as it allow for maximum opportunity for Google demand to increase the price of each impression.
When creating AdSense or Ad Exchange line items a Web property alias must be selected. This will offer the choice of any accounts that have be linked to the Ad Manager account and determines which account will be used to serve impressions into that line.
When two competing Dynamic Allocation lines are eligible for an impression, problems can arise that decrease performance and lowers revenue. It is strongly recommended that AdSense monetization on ad units is disabled and AdSense line items suspended when ad Exchange lines are in place.
Network (Priority 12)
Network line items are given a goal of a percentage of “remaining impression”, ie those not taken by guaranteed line item types. A rate is set, using a CPM, CPC or CPD figures. This rate is used both for reporting and as a value to compete against if Dynamic Allocation line items (AdSense or Ad Exchange) are booked. For example if a Network line with with a $2 CPM is eligible to serve, a Dynamic allocation line would need to be able to pay greater than $2 to beat it.
Network line items used to be a popular choice for serving ad networks, but this use has diminished with the rise of header bidding.
Bulk (priority 12)
Bulk lines are similar to Network, but have an impression limit rather than a percentage. This limit can be set in either impressions or clicks. The price of a Bulk line affects dynamic allocation performance in the same was as Network lines.
Price Priority (Priority 12)
Price priority offers a flexible way of trafficking lines based on their value. Before header bidding, Price Priority was the main way to get dynamic allocation competing against other demand. Price priority allows for an optional daily or lifetime limit to be set. This can be based on either impressions of clicks.
House (Priority 16)
House lines are served when no other lines are eligible. They are used as an “ad of last resort”, often serving non-revenue generating ads. A CPM or CPC value can be set for Dynamic Allocation to compete against
Click-Tracking Only (No priority)
The click-tracking type is a little different, in that lines of this type don’t compete with other types. This is mostly used for tracking clicks through fixed assets on a page that are handled outside of the Ad Manager auction.
Guaranteed vs Non-Guaranteed line items
The ten line item types that have a priority can be considered to either be “Guaranteed” or “Non-Guaranteed lines”. Guaranteed line items are those where Ad Manager reserves inventory for their delivery. They have set goals in terms of impressions, clicks or impression share and Ad Manager will ensure that these are met at the cost of non-guaranteed lines.
Non-Guaranteed line items serve into inventory that is available only when the obligations of the Guaranteed lines will be met. These are essentially remnant lines ensuring that left over impressions get filled.
|Standard (all 3 types)||Network|
How the priority types interact
When ad manager receives an impression request it first looks for lines that have targeting criteria that match the request. Targeting criteria, such as creative sizes, geo or key-values ensure that the right line items are deemed eligible for each impression. Ad Manager then looks at each eligible line item in priority order (from lowest priority score to highest) to determine which to show.
For guaranteed line items (Priority 4 to 10) this is largely based on how delivery is pacing against the line item goals. For example, a Sponsorship line item with a goal of 100% of impressions would prevent any lower priority line item from showing. If the impression goal was changed to 50% then lower priority lines would show, but only if they would not stop the sponsorship line reaching it’s goal.
Network, Bulk and Price Priority lines are all priority 12. When there are multiple eligible lines at the same priority then the line shown is determined by price, which the highest price line winning every time (example, a $2.00 price priority line will never win an impression against a $1.00 price priority line).
Line item types that compete against dynamic allocation
If you have Dynamic Allocation or First Look enabled then things are handled slightly differently. Dynamic allocation gives Google the option to outbid the highest line item. If there were a price priority line eligible at $2.00, Dynamic Allocation would need to be able to pay at least $2.01 to win the impression (and hopefully more). Standard Dynamic Allocation lines will only complete against other Priority 12 line items.
|Dynamic Allocation||Enhanced Dynamic Allocation||First Look|
|Sponsorship||No||No||Only when on pace|
|Standard||No||Only when on pace||Only when on pace|
Mat has been supporting content creators on the web since 1996. As Co-founder of OKO Digital, Mat became the first person in the UK qualified to AdSense partner status and repeated this first with Google Certified Publishing Partner programme.