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Xandr Header Bidding Wrapper Code of Conduct

Last updated April 24, 2017.

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  • Wrapper: any technology layer that facilitates bids from demand partners being passed into the ad server.
  • Demand partner: any party that is willing to provide a price to be paid to the publisher for a given impression, and is integrated into the wrapper.
  • Publisher: the party who is integrating the wrapper into their page.

Auction Logic

  • The wrapper must not modify bids from demand partners.
  • The wrapper must not bias bids from demand partners unless requested by the publisher.
  • The wrapper must provide equal opportunity for all demand partners to bid, either by requesting bids simultaneously or by randomizing the order in which they are called.
  • The wrapper must send all demand returned within the Publisher-configured timeout to the ad server.
  • The ad server must make the final choice of what bid wins.
  • The wrapper must provide a mechanism to validate that submitted bid responses were sent to the ad server.
  • Auction logic and methodology must be disclosed to all parties prior to commencement of a commercial relationship, and any change to auction logic must be disclosed prior to its implementation.
  • The wrapper must provide a mechanism for publishers and demand partners to validate auction logic.
  • The wrapper must not favor any demand partner in any way, including any demand that is provided by a bidder that is also hosting the wrapper.

Data and Transparency

  • The wrapper must segregate demand data so there is no opportunity for demand partners to have access to other bids.
  • The wrapper must pass all available information to each demand partner.
  • The wrapper must not collect and store publisher or demand partner information except in the process of passing information to demand partners, validating auction mechanics, or providing aggregated reporting to publishers.
    • o This includes bid stream information, user information, and publisher first party data.
  • Demand partners must not record, use, or sell publisher data without permission from the publisher and the demand partner.
  • The wrapper must be able to provide mechanical data relating to each auction: who was called, who responded on time, and who responded late.
  • If the wrapper charges fees, the fee structure should be disclosed to all parties involved in the setup.

User Experience

  • The wrapper must minimize the impact on the user's web browsing experience.
  • The wrapper must not allow any demand partners to have any blocking or synchronous steps in the process of eliciting a bid.
  • Publishers must set timeout periods, and the timeouts should be consistent across all demand partners within a given auction.
  • The wrapper must reject any bid responses received after the conclusion of the timeout period.
  • The wrapper must send bids to the ad server as soon as all demand partners have responded or the timeout has been reached.