RTBlintAlpha
Loss reason 103: Lost to a Bid for a Deal
What it means
A deal-backed bid took priority over this open-auction bid.
The exchange reports this code by expanding the ${AUCTION_LOSS} macro in the bid's loss notice URL (lurl). A bidder that does not set lurl never sees it, and never learns why it lost.
What to do about it
The bid was valid and lost on price or eligibility: below a floor, outbid, beaten by a deal, or seat-blocked. The response side is fine; the lever is bidding strategy. Log AUCTION_MIN_TO_WIN wherever the exchange expands it, and check floors and deal terms in the request before pricing.