# BidSwitch OpenRTB Differences¶

Even though the BidSwitch Real-time Bidding Protocol v5.3 is based on the latest OpenRTB Protocol Specification V2.5, differences exist between the two. Those differences are outlined in this section.

## Bid Request Differences¶

The BidSwitch protocol differs in the following ways.

• bcat accepts additional non-IAB Blocked Advertiser Categories.

• native.request is an object. The OpenRTB version uses a string and passes a serialized object.

• user.buyeruid uses a lowercase IDFA, or Android ID for in-app traffic, if the user cookie ID is not known.

## Bid Response Differences¶

The BidSwitch protocol differs in the following ways.

• ext.protocol is required.

• seatbid.bid array can have a maximum of two elements.

• seatbid.seat is required if wseat is present in the bid request.

• seatbid.bid.adm may or may not contain the win price macro depending on the protocol version, bid request parameters, and nurl field usage. See the 5.x Updating Overview section for details. The field may not be used for submitting VAST or DAAST documents.

• seatbid.bid.iurl is required for banner bids.

• seatbid.bid.price is required.

• One of either seatbid.bid.adid or seatbid.bid.crid is required.

• seatbid.bid.adomain is required.

• seatbid.bid.cid is required for a number of Suppliers.

• seatbid.bid.cat is required for a number of Suppliers.

• seatbid.bid.ext.advertiser_name is required for a number of Suppliers.

• seatbid.bid.ext.agency_name is required for a number of Suppliers.

• seatbid.bid.ext.duration is required for a number of Suppliers.

• seatbid.bid.ext.vast_url may be used to supply the VAST document in any video bid. It is required to be used for video bids if the video.ext.vast_url_rq bid request field is set to 1. The VAST document should not contain win price macros

• seatbid.bid.nurl

• Should NOT be used for submitting creative markup, and it cannot contain a win price macro if seatbid.bid.adm contains one.

• May be used to supply the VAST document if the video.ext.vast_url_rq bid request field is set to 1. The VAST document should NOT contain win price macros.