What is a seat ID?
A Seat ID is a unique number, that identifies an advertising buyer on OpenRTB. It is usually used to authorize a particular buyer or set of buyers to buy in particular inventory, through Deals.
All organizations in mediasmart have their own Seat ID that you can copy and paste from the organization area in your account.
Do you need a Seat ID or not to bid on a Private Deal?
It depends on the AdExchange/SPP.
For all the exchanges except Google and Xandr, we always bid with a specific seat ID for all the campaigns you run within your organization. The SSP/exchange will match any Deal IDs created for you with the Seat ID assigned to you in our system. This is a Seat ID created by us (it can be provided by your account manager in mediasmart), and bidding with it does NOT mean these exchanges will invoice you directly. That would only be the case if there is a specific agreement between yourselves and the exchange for that to happen.
In the case of Google, we normally bid with mediasmart´s Seat ID in Google´s system, unless you specifically want us to bid with your own seat ID at Google (in this case, it would be provided to you by Google and not by mediasmart). You would only use your own Google Seat ID if you want to be invoiced directly by Google. Otherwise, you just need to tell publishers that when they create deals for you in the Google interface, they need to create them for mediasmart.
Step-by-step
Select the Supply partner: