Auction Overlap can happen when you have two ad sets running at the same time, targeting similar audiences. When their ads are about to enter the auction, Meta first chooses the ad with the highest total value. That ad will be the one that enters into the auction. The other won’t be considered. Meta does this to prevent you from bidding against yourself. When there’s too much Auction Overlap, it can result in higher costs or under delivery.
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Facebook Audience and Auction Overlap and When It’s a Problem
