{"page":"/blog/openrtb-2-6-explained","modified":"2026-11-10","license":"https://creativecommons.org/licenses/by/4.0/","columns":["Object","Field","Type","Meaning","Notes"],"rows":[["BidRequest","id","string, required","Auction ID set by the exchange","The response must echo it; it fills the ${AUCTION_ID} macro"],["BidRequest","imp","object array, required","Impressions on offer","At least one Imp"],["Imp","id","string, required","Impression ID inside this request","Bid.impid must match it"],["Imp","tagid","string","Placement or ad tag ID","Useful for debugging and buyer optimisation"],["Banner","format","object array","Sizes the slot accepts","Here 300x250 and 300x600"],["Banner","pos","integer","Ad position, AdCOM list \"Placement Positions\"","1 = above the fold"],["Banner","battr","integer array","Blocked creative attributes, AdCOM list","3 = expandable (automatic), 8 = pop"],["Imp","bidfloor, bidfloorcur","float, string","Minimum CPM and its currency","Currency defaults to USD if absent"],["Imp","secure","integer","1 = creative must use HTTPS","Non-secure markup is rejected"],["Metric","type, value, vendor","string, float, string","A metric the exchange supplies, such as predicted viewability","Names agreed in advance; \"EXCHANGE\" when the exchange computed it"],["Pmp","private_auction","integer","0 = open auction bids also accepted","1 would restrict bidding to the listed deals"],["Deal","id, bidfloor, bidfloorcur, at, wseat","string, float, string, integer, string array","The deal ID, its floor, auction type and allowed seats","Deal.bidfloorcur does not inherit Imp.bidfloorcur; at 3 would mean a fixed deal price"],["Site","domain, page, ref","string","Where the ad will appear and the referrer","page is the full URL"],["Site","cattax, cat, pagecat","integer, string arrays","Site and page categories and the taxonomy used","9 = Content Taxonomy 3.1; 52 = Business and Finance; 391 = Personal Finance"],["Publisher","id, name, domain","string","The seller of the impression","id is the seller_id in the exchange's sellers.json and matches the last schain node"],["Content","language","string","Content language, ISO 639-1","Use langb instead for BCP 47 tags"],["Device","ua","string","Raw user-agent header","Still recommended for compatibility"],["Device","sua","object","Structured user agent from client hints","source 1 = only low-entropy hints were available"],["Device","ip","string","IPv4 address closest to the device","Truncated here, a common practice under GDPR"],["Device","devicetype, language, js, dnt","integer, string, integer, integer","Device type, browser language, JavaScript support, Do Not Track","devicetype 2 = personal computer"],["Geo","country, type, utcoffset","string, integer, integer","ISO 3166-1 alpha-3 country, location source, minutes from UTC","\"DEU\"; type 2 = derived from IP"],["User","id, buyeruid","string","Exchange user ID and the buyer's synced ID","buyeruid comes from cookie sync"],["User","consent","string","TCF TC string when GDPR applies","This is the example string from the GPP specification"],["EID","source, inserter, mm, uids","string, string, integer, object array","One extended ID: here SharedID (pubcid.org) added by the publisher","mm 4 = observed first-party ID; atype 1 = browser or device ID"],["Source","fd","integer","Who makes the final sale decision","1 = an upstream source, typical for header bidding"],["Source","tid","string","Transaction ID shared by every exchange that sees this impression","Lets buyers spot the same impression arriving twice"],["SupplyChain","complete, ver, nodes","integer, string, object array","Every seller between publisher and buyer","One node = a direct sale"],["SupplyChainNode","asi, sid, hp","string, string, integer","Exchange domain, seller account, payment flag","hp 1 = this node handles payment"],["Regs","gdpr","integer","1 = GDPR applies","Omitted means unknown"],["Regs","gpp, gpp_sid","string, integer array","Global Privacy Platform string and the section that applies","Section 2 = EU TCF v2"],["BidRequest","at","integer","Auction type","1 = first price, 2 = second price plus"],["BidRequest","tmax","integer","Milliseconds the exchange will wait","Includes network latency"],["BidRequest","cur","string array","Currencies accepted for bids","ISO 4217 codes"],["BidRequest","cattax, bcat, badv","integer, string arrays","Blocked advertiser categories and domains","8 = Ad Product Taxonomy 2.0; 1361 = Gambling, 1544 = Tobacco"]],"sourceUrls":[[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[]]}