Multiple Deal Seats

[capitalfact]

In current spec for BidResponse there seems to be some ambiguity around multiple bids but only one possibility to set seat

Object in question: (http://www.iab.net/media/file/OpenRTB-API-Specification-Version-2-3.pdf), see SeatBid definition (4.2.2).

We may have one seat but multiple bids. This seems like a limitation in the following scenario:

BidRequest

• wseats on impression level ["A", "B"]
• Two deals in pmp object, with wseat "A" and "B" respectively.

Client decides to bid on both deals.
BidResponse

• Contains two Bids with respective dealid's.

Questions:

1. Is this in fact a limitation or by design?
2. How should I proceed in the above scenario?

Can provide further details if required.