In preparation for improvements to CPA bidding in AdWords, starting October 26, 2015 , we'll perform a one-time removal of inactive ad group-level CPA bids.
What's an inactive ad group CPA bid, you ask? An ad group-level CPA bid is inactive if the ad group's effective bidding strategy is not a CONVERSION_OPTIMIZER strategy. This includes CPA bids on ad groups whose effective bidding strategy is TARGET_CPA, since the target for such ad groups is specified at the strategy level. The effective bidding strategy is the ad group-level strategy, if specified. Otherwise, it’s the bidding strategy set at the campaign-level.
How this change impacts the AdWords API
After the one-time removal of inactive CPA bids, there are two categories of ad groups you'll want to review:
Ad groups from which inactive CPA bids were removed: For these ad groups, the AdGroup object will no longer have a CpaBid in the bids attribute of its ad group-level BiddingStrategyConfiguration. Therefore, if you change the effective bidding strategy of these ad groups back to a CONVERSION_OPTIMIZER strategy, you will have to add a new CpaBid to the ad group’s BiddingStrategyConfiguration for your ads in the ad group to serve. You will only have to make this change once .Ad groups you change from TARGET_CPA to CONVERSION_OPTIMIZER: AdWords will no longer copy the TargetCpaBiddingScheme.targetCpa value to a CpaBid on the ad group's bidding strategy configuration. Therefore, you will not automatically get the TARGET_CPA strategy bid if you transition to CONVERSION_OPTIMIZER. If the ad group's bidding strategy configuration already has a CpaBid, then CONVERSION_OPTIMIZER will use that bid. Otherwise, you will have to add a new CpaBid to the ad group BiddingStrategyConfiguration before ads in your ad group will serve.
How this change impacts bidding
Since the CPA bids being removed are inactive, this change will have no impact on bidding or ad serving.
What you should do
If you are interested in inactive CPA bids for CONVERSION_OPTIMIZER bidding strategies, download the current bids using AdGroupService before the removal date.
More bidding resources
Still have questions? Feel free to visit us on the AdWords API Forum or our Google+ page .
Josh Radcliff , AdWords API Team
