NYSE filed for immediate effectiveness to amend elements of NYSE Rule 72, Bids and Offers and Allocations of Executions, that can currently dis-incentivize aggressive displayed quoting by permitting pegging e-Quotes to eliminate the priority to which a non-pegging e-Quote might otherwise be entitled.

As currently provided under Rule 72(a)(ii), a bid or offer is considered the "setting interest" when it is established as the only displayable bid or offer made at a particular price and is the only displayable interest when such price is or becomes the Exchange best bid or offer ("BBO").   Setting interest is entitled to priority for allocation of executions at that price, as provided for under NYSE Rule 72. In this regard, and as currently provided for under NYSE Rule 72(a)(ii)(G), if nonpegging interest is the setting interest, it retains its priority even if joined at that price by a pegging e-Quote. If, however, at the time non-pegging interest becomes the Exchange BBO, an e-Quote is pegging to such non-pegging interest, all such interest is considered to be entered simultaneously and, therefore, no interest is considered the setting interest.

For further details, and probably a clearer explanation of rule and its changes, go to:  [NYSE Rule Filing 11-60, 11/21/11].