Hello,
If you are using the AdWords API, you could use
CampaignCriterionService then set criterion as
MobileAppCategory and then set
isNegative to true.
If you are using Google Ads API Beta, then you have to use
CampaignCriterionService then set criteria as mobile_app_category and set negative field of the
CampaignCriterion to true to exclude mobile_app_category criterion for that campaign. Please let me know if you have any further questions.
Regards,
Sai Teja, Google Ads API Team

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