Opening/Closing Price Message Fields

The Opening/Closing Price message is used to indicate the Opening or Closing price of a security on any of the Cboe exchanges and the primary listing market. An Opening/Closing Price message will be sent whenever the opening or closing price of a security is established. The opening or closing price is established once across all Cboe exchanges (not per-exchange). Additionally, an Opening/Closing Price message will be sent after it is received from the CTA or UTP SIP once the delay period has expired, currently 15 minutes.

• For Cboe listed securities, the opening and closing prices will be sent when they are received from the listing market and again when received from the SIP and the delay period has expired.
• For non-Cboe listed securities, the opening price of a security is defined as the first eligible trade received that occurred on or after 9:30:00 from any Cboe exchange. If no eligible trade is received by 9:35:00, no opening price will be reported from a Cboe exchange. A message will also be sent after the official open from the listing exchange is received and the SIP delay period has expired with Market Center set to C or U.
• For non-Cboe listed securities, the closing price of a security is the last eligible trade received when any Cboe exchange timestamp exceeds the end of the regular session (normally 16:00:00). If no eligible trade has occurred prior to the close, no closing price will be reported from a Cboe exchange. A message will also be sent after the official close from the listing exchange is received and the SIP delay period has expired with Market Center set to C or U.

The Market Center will identify the Cboe exchange that set the Opening or Closing Price for this security.