Cboe EDGA Displayed and Non-Displayed Midpoint Discretionary Order

Midpoint Discretionary Order (MDO) is a blended order type that incorporates the characteristics of Primary Peg, Midpoint Peg and Discretionary orders. Members can use MDOs to post displayed or non-displayed liquidity at the National Best Bid/National Best Offer for Buy/Sell orders with a discretionary range extending to and including the NBBO midpoint. MDOs do not execute at a price more aggressive than the NBBO midpoint.


  • Displayed MDOs to Buy/Sell are displayed at and pegged to the NBB/NBO with a non-displayed discretionary component.
  • Non-Displayed MDOs to Buy/Sell are non-displayed at and pegged to the NBB/NBO with a non-displayed discretionary component.
  • MDOs can be entered with or without a limit price.
  • MDOs have discretion to execute at prices ranging to and including the midpoint of the NBBO, consistent with their limit price.
    • If an MDO’s limit price does not allow discretion to the midpoint of the NBBO, then the MDO will have discretion to its limit price.
  • The discretionary range will only be used if necessary. Incoming contra side orders that cross the spread will execute at the MDO’s NBB or NBO resting price.


MDOs are charged $0.0003 per share when executed at the National Best Bid or Offer. MDOs are FREE for executions in the discretionary range.

MDO Execution Fee Code Fee
Adds/Removes liquidity at the discretionary range DM, DT FREE
Adds/Removes liquidity at Displayed/Non-Displayed Price DA, DR $0.0003


Please contact the Cboe U.S. Equities Trade Desk (tradedesk@bats.com, 913.815.7001) or your Director of Sales with any questions. We appreciate your continued support of Cboe and look forward to earning more of your business.