Hi Joseph,
You should be able to get the bid strategy ID by using the get method in
CampaignService. You will need to select the "BiddingStrategyId" field in your
selector with a filter on the Campaign.Id field for the campaign you are trying to retrieve the bidding strategy for. The ID should be returned if you have Portfolio strategy associated with the campaign.
Let me know if you have any additional questions.
Regards,
Danica, Google Ads API Team

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