IEX Router

The IEX Router offers the ability for users to interact with liquidity on both the IEX Exchange Order Book and away venues. IEX’s Speed Bump and low latency network are designed to protect routing orders from information leakage while maximizing fill rates.

Once posted to the IEX Exchange Order Book, routable orders re-sweep to capture Protected Quotations that lock or cross the order’s limit. The IEX Router is operated by IEX Services LLC. IEX Services’ Market Participant Identifier (MPID) is IEXG.

Router Functionality

The IEX Router sends orders to the IEX Exchange Order Book to check for available shares in a way designed to minimize market impact, before sending any remainder to destinations on the System routing table, which may include the IEX Exchange Order Book. If shares remain unexecuted after routing, they are posted on the Order Book or canceled, in accordance with User instruction. Once posted on the Order Book, the unexecuted portion of such order is eligible for the re-sweep behavior.

If the limit price of a resting routable order is crossed or locked by one or more Protected Quotations, the IEX Router removes all or a portion of the order from the IEX Exchange Order Book, respectively, and routes to the Protected Quotation(s).

IEX Check with Minimal Market Impact

The IEX Router “checks” IEX Exchange by routing the entire order with either an FOK (“Fill-or-Kill”) or IOC (“Immediate-or-Cancel”) time-in-force to the IEX Exchange Order Book. Depending on the size of the order and the cumulative shares from Protected Quotations at the NBBO (“PBBO”), the IEX Router will choose one of the techniques below to minimize market impact (i.e., liquidity fade) from any fills received on the IEX Exchange Order Book.

Undersized Order

If the routable order size is substantially smaller than the cumulative shares at the PBBO, the IEX Router checks the IEX Exchange Order Book to the PBBO with a standard IOC (no minimum quantity condition) because the risk of missing shares due to liquidity fade is low.

All Other Orders

If the order is not undersized, the IEX Router checks the IEX Exchange Order Book to the PBBO using an FOK order (i.e., minimum quantity equal to order size), meaning the order must be completely filled or no execution occurs, so as to avoid information leakage that could occur in the case of partial execution.