Atomic settlement

The chain

When the taker accepts your quote:

1. Accept — nothing of yours moves. Your committed allocations already are your side of the trade; the accept locks the quote in the desk's book and opens the settlement window. You are not involved.
2. Allocations — the taker signs its own side, returned by its accept, the same way you signed your quote: committed token-standard v2 allocations naming the same settlement; the desk adds the operator's fee receipt. trade.step {step: "allocated"} fires once every allocation of the trade is on the ledger.
3. Settle — the operator, as the settlement executor, submits one Canton transaction carrying one SettlementFactory_SettleBatch per instrument registry: both legs of the swap and the desk fee move together. Either the whole trade happens, or none of it does. There is no partial fill and no leg risk.

The fee

The desk fee is paid by the maker to the operator, in the pair's quote instrument:

fee = qty × price × feeBps / 10000   (floored to 10 decimal places)

feeBps is stamped on the RFQ at creation — you see it in rfq.created before you quote, so price it in. Your quote-asset allocation carries it: on a SELL RFQ (you buy the base) it is locked together with the notional you pay; on a BUY RFQ (you sell the base) it sits in the allocation that receives the notional, and must still be covered by quote-asset holdings you already have — the notional arrives only with the settle itself.

Proof

trade.settled delivers the final TradeDto whose ledger object is your on-ledger proof:

• updateId — the Canton update id of the atomic settle transaction;
• receiptCids — the contract ids of the allocations the batch consumed (yours, the taker's and the operator's).

Both are also available later via GET /maker/trades.

When settlement fails

trade.failed {tradeId, rfqId, reason} ends the trade: the taker could not fund its leg, the settlement window expired (the taker never signed its side), or your allocation is gone. Nothing has moved — atomicity cuts both ways. Your quote is revoked and the desk cancels the trade's allocations, so your holdings are free again; the RFQ stays open until its deadline, and the taker may accept another quote. Your own side was locked at quoting time, so short of your allocation disappearing, a failure is not yours to prevent.