Gemini is rolling out a new trading tool that brings Wall Street-style execution mechanics to prediction markets. The exchange’s Custom Combos feature, now live for beta testing in its sandbox environment, lets market makers submit sealed bids on multi-leg prediction market contracts through a Request-for-Quote API.
How the system actually works
The RFQ process runs on a tight clock. Market makers get a 1-second window to submit their quotes after a request comes in. The requester then has 5 seconds to accept the best bid. Finally, the winning maker gets a 1-second “last-look” confirmation period to finalize the trade.
That entire lifecycle runs through a series of defined states: OPEN, PENDING_ACCEPTANCE, CONFIRMING, and FINALIZING. The whole thing wraps up in roughly 7 seconds.
The sealed-bid design means competing market makers can’t see each other’s quotes. Only the winning bid gets disclosed after the auction concludes.
