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Delivery Modifier allocates spend to specific inventory in real time based on the set rules. For example, you can use a Delivery Modifier to spend 50% of your budget on a particular Domain List, 25% on a specific Publisher, and 25% on any other inventory that meets you targeting criteria.

See our buyer guide to learn about how to use them to deliver against inventory that drive the highest CTR.

A Delivery Modifier can be associated with one or more Line-Items or Campaigns. Campaign level Delivery Modifier applies to any Line-Items owned by the Campaign that do not have associated Delivery Modifiers.

How it Works

Delivery Modifiers are composed of several Terms (between 1 and 100), which define pools of inventory and how much of the Line Item or Campaign’s budget should be spent on each. A Term’s Weight is used to define how much budget that Term receives relative to the others.

Budget Caps impose strict limits on the amount of spending that can be allocated to a given Term. Using budget caps provide the most control but can risk under delivery if inventory is scarce.

Pacemaker, Beeswax’s pacing system, controls the pacing and budget allocation of all Delivery Modifier Terms. Each term is paced independently according to its allocated budget. Delivery Modifiers work in tandem with pacing, so Line-Items or Campaigns must have pacing enabled to use this feature.

Delivery Modifier Terms are paced using the Line-Item’s Pacing settings:

• Daily, Lifetime, or Flight 
• Spend or Impressions 

Weighting Terms:

Term weights must obey the following restrictions.

• Maximum value of a Term weight is 100
• Minimum value of a Term weight is 0.01
• Minimum value of Fallback weight is 0.

Pacing Rules:
Line-Item pacing takes precedence over the pacing of any given Delivery Modifier Term.

• If a Delivery Modifier Term is under delivering, its unspent budget will be re-allocated to other Terms so that the Line Item delivers on schedule.
• When one Term’s budget is reallocated due to under delivery, that budget will only be lost until the Term is able to spend on pace again. Once inventory is available, a Term will get back to delivering on pace in 12-24 hours.
• Budget allocations for each Delivery Modifier Term are re-calculated every hour and the bid probabilities that control pacing are recalculated every ~60 seconds.

Term Priority Effect on Pacing and Budget Re-allocation

• Priority controls which Term can be used when an RTB auction matches multiple Terms. The Term with highest priority will count the impression toward its budget unless it is pacing up to schedule. In that case the impression will be counted against the budget of the next highest priority Term that matches the auction features. 
• Priority has no bearing on budget re-allocation across Terms. It only controls which Term counts a given impression. 

• In some circumstances, Fallback Weight may overlap with expressed Modifier terms.