Beginning in May, 2021 we will enforce a requirement that temporary IDs be unique for all objects in newly created listing groups (used for Hotel Ads and Shopping Ads in the Google Ads API) and product partitions (used for Shopping Ads in the AdWords API). This change will affect all versions of both the AdWords and Google Ads APIs.

Temporary IDs must be unique across an entire mutate request–even if the objects are in separate listing group trees or product partition trees.

In order to avoid unnecessary breakages, API users should update their applications to ensure that all temporary IDs used in individual requests are unique.

Here is a snapshot of the expected behavior for requests that continue using non-unique temporary IDs:

API and mutate method	Current Behavior	New Behavior
BatchJobService with the Google Ads API	Customers will receive a non-specific error, meaning it may not specify that the issue is related to temporary IDs.	Customers will start receiving failed operations that contain the error: MutateError.MUTATE_ERROR_TEMP_ID_ALREADY_EXISTS
BatchJobService with the AdWords API	Customers will receive a non-specific error, meaning it may not specify that the issue is related to temporary IDs.	Customers will start receiving failed operations that contain the error: NewEntityCreationError.DUPLICATE_TEMP_IDS
AdGroupCriterionService or GoogleAdsService.Mutate with the Google Ads API	Customers will not receive an error.	Customers will start receiving the error: MutateError.MUTATE_ERROR_TEMP_ID_ALREADY_EXISTS
AdGroupCriterionService with the AdWords API	Customers will not receive an error.	Customers will start receiving the error: NewEntityCreationError.DUPLICATE_TEMP_IDS

If you have any questions or need additional help, contact us via the forum or at [email protected].
- Ben Karl, on behalf of the Google Ads API Team