Introduction

Note that this specification will be the standard Complex top of book specification to be used for all Cboe-affiliated Options exchanges.

Cboe customers may use the Complex Multicast TOP protocol to receive real-time top of book quotations from Cboe.

The quotations received via Complex Multicast TOP provide an aggregated size and do not indicate the size or number of individual orders at the best bid or ask. The Complex Multicast TOP protocol also provides last trade price and size and cumulative volume data.

Complete depth of book market data can be received via the US Options Multicast PITCH protocol.

TOP cannot be used to enter orders. For order entry, refer to the appropriate Cboe FIX or BOE Specification.

All current versions of the US Options Complex Multicast TOP feed are WAN-shaped (maximum 100 Mb/s) and available from both of Cboe's datacenters. Customers may choose to take one or more of the following Multicast TOP feeds depending on their location and connectivity to Cboe.