Advertisers can also learn about their Pmax search impressions via Search Term Insights, a tool released more recently that can also be used for non-Pmax Google campaigns.

Three buyers told Adweek that they did not realize that Pmax Placement Reports did not include Search inventory.

“Google’s explanation and the way they surface the data is not very clear,” Rigas said, noting that clearer Placement Reports could help buyers with attribution, brand impact and creative optimization. “So Google being so opaque with that data is not ideal.”

Google also does not break down Pmax inventory by spend or performance, only by impressions, Lovallo said.

“The reporting for normal campaign types is way more granular,” Lovallo said. “That’s kind of by design. They sort of built Pmax to be a black box.”