Reduce product and sensitive category filtering

All bid responses on Authorized Buyers are screened before they enter the auction. During the screening process, some bids are rejected from entering the auction. This is called bid response filtering. Filtered bids represent lost bid opportunities. Learn more about why bids may be filtered.

On this page

• Common reasons for bid filtering
• Reduce product and sensitive category filtering
• Choosing the correct taxonomy
• Technical support

Common reasons for bid filtering

While there are various reasons why bid response filtering may occur, two types of increased filtering are common:

• Excluded sensitive category detected: The bid is filtered because one or more sensitive categories were excluded by publisher settings or Google policy. This filtering reason corresponds to creative status code 14.
• Excluded product category detected: The bid is filtered because one or more detected product categories were excluded by the publisher through the bid request. This filtering reason corresponds to creative status code 15.

Publishers can block categories of creatives from serving on their web sites and apps. We provide a clear list of prohibited ad categories within each bid request. Any creative that is identified as pertaining to a blocked category will be filtered, preventing it from entering the auction. Publishers configure their category blocks using Google-specific product and sensitive categories. Google’s OpenRTB implementation uses IAB Content 1.0 for communicating category blocks to bidders as the default setting.

Because publishers and bidders use two different classification systems, categories are translated to and from IAB Content 1.0 when communicating with bidders. This conversion is imprecise so it’s impossible for bidders using IAB Content 1.0 to completely avoid bid filtering. 

OpenRTB bid requests indicate these categories with BidRequest.bcat, while BidRequest.cattax indicates the taxonomy used by bcat to indicate IAB Content 1.0. 

In the bid response, bidders should declare relevant categories for their bid using BidResponse.seatbid.bid.cat. Bidders can indicate the taxonomy used in cat with  BidResponse.seatbid.bid.cattax. If cattax is omitted, Google will attempt to read cat using the bidder’s default taxonomy.

Reduce product and sensitive category filtering

We can minimize bid filtering caused by Google and IAB content taxonomy differences in two ways.

Reading Google taxonomies in bcat

Google supports a new account setting where bidders can choose whether bid requests use IAB Content 1.0 (the default) or Google Ad Category Taxonomies, which include product, restricted, and sensitive categories. If your account is configured to use Google Ad Category Taxonomy, BidRequest.bcat will be populated with product and sensitive categories. In a future update, this will also include restricted categories.

Google products and sensitive categories

Learn more about Google products and sensitive categories.

Avoid filtering with the IAB product and sensitive taxonomies in the Creatives API

For bidders continuing with IAB Content 1.0 (cattax = 1), the Creatives API provides detected Google categories mapped to IAB categories. This enables comparison with the bcat field. Bidders can compare the detected product and sensitive categories in the API to the bcat field to avoid filtering.

Choosing the correct taxonomy

Both taxonomies are well supported. We recommend bidders choose the taxonomy that best aligns with your priorities. 

Consider these potential trade-offs:

• Google Ad Category Taxonomy more precisely communicates the publisher’s preferences. Bidders who are willing to integrate with it can achieve a lower bid filtering rate than bidders who integrate with IAB Content 1.0.
• IAB Content 1.0 is standardized and widely used across the ad tech industry. Because of this, we anticipate that it may be easier for many bidders to use IAB Content 1.0, though bid filtering rates will likely be higher.

Technical support

For technical support or questions about the process:

• Review the developer content:
  • OpenRTB Migration Guide – Ad Categories
  • Authorized Buyers Real-time Bidding API Creatives Guide – Select your preferred taxonomy
• Contact your sales representative or create a customer ticket for help with your account configuration, product and UI questions, and some technical support. If you don’t have an assigned Account Manager, use the contact form to create a customer ticket.
• The Authorized Buyers support forum provides public answers about the RTB protocols or APIs. You can search for similar questions to find answers to your questions. 
• Use the Technical API email support for answers to private questions about the RTB protocols or APIs. Unlike the support forum, questions here are private and can include details about your account that may assist with investigating your question or issue.