Welcome to OpenYield FIX Connectivity.
Connect directly to the OpenYield marketplace — an SEC-registered Alternative Trading System for U.S. Treasury, agency, municipal, and corporate bonds. Unlike traditional bond venues, OpenYield operates a firm, order-based market with no last look — bringing equity-style execution certainty to fixed income. Consume live market data and send orders over FIX 4.4, across both our live order book and our Request for Order (RFO) protocol, which enables RFQ-style interactions directly into the book.
New to OpenYield FIX?
Start here. Getting Started shows where to begin for each way of connecting: the sessions, certification groups and pages for your role, and how Summon requests work.
Connectivity requires a signed OpenYield Subscriber Agreement.
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This document describes the FIX connectivity specification for OpenYield Trading LLC (“OpenYield”). Subscribers must support FIX 4.4 and initiate all connections; production connections use stunnel (TLS), AWS PrivateLink, or AWS Direct Connect (see Connectivity). OpenYield offers five FIX session types, and additional instances of a session are available on request:
| Session | Suffix | Purpose |
|---|---|---|
| Market Data | -MD |
Equity-style top-of-book feed including best bid, best offer, daily high and low, and trade prints. |
| Order Book | -OB |
Full depth of the live order book for clients that need complete order book visibility. |
| Trading | -TR |
Live market orders and executions, for both providing liquidity (Limit Order or Quote) and taking liquidity (Market Order). |
| Drop Copy | -DC |
Copies of fill execution reports, plus post-trade fill cancels and corrections. |
| Summon | -RQ |
RFQ-equivalent session to send Summon requests, with or without a limit, and to receive requests and respond with quotes. Fills arrive on TR and DC. |
Use Market Data for top-of-book data and Order Book for full-depth data. New orders are only processed on the Trading (TR) and Summon (RQ) sessions. The following workflows are supported:
| Workflow | Description |
|---|---|
| Market Maker | Post Limit Orders or Quotes to the Central Limit Order Book. Crossing orders are matched and filled; any residual quantity remains on the book. |
| Market Taker | Receive MD or OB feeds and send Market Orders or IoC Limit Orders to fill against book liquidity from the best level down — no RFQ or counterparty quote required. |
| Summon | Send a Summon (537=0) to invite quotes into the order book. Responders post, update, or cancel quotes for 30 seconds after the request; crossing quotes execute firmly. |
| Summon with a limit | Send a Summon with a limit (537=1 and a price); 5 seconds after the request, OpenYield places it on the book as a limit order, where it executes against crossing quotes. |
| Legacy RFQ | For subscribers who don't read the order book: send a request with 537=1 and receive the responses as quotes on RQ 5 seconds later, then accept one. See Legacy RFQ. |
| Post Trade | Receive execution confirmations, post-trade cancels, and corrections via the Drop Copy (DC) session. |