The following definitions apply to the Equity Rules for the trading of securities on PSX.

(a) The term “PSX,” or “System” shall mean the automated system for order execution and trade reporting owned and operated by the Exchange. The Exchange will operate PSX as an automated trading center for purposes of Rule 600(b)(4) of Regulation NMS. PSX comprises:

(1) a montage for Quotes and Orders, referred to herein as the "PSX Book", that collects and ranks all Quotes and Orders submitted by Participants;

(2) an Order execution service that enables Participants to automatically execute transactions in System Securities; and provides Participants with sufficient monitoring and updating capability to participate in an automated execution environment;

(3) a trade reporting service that submits "locked-in" trades for clearing to a registered clearing agency for clearance and settlement; transmits last-sale reports of transactions automatically to the National Trade Reporting System, if required, for dissemination to the public and industry; and provides participants with monitoring and risk management capabilities to facilitate participation in a "locked-in" trading environment; and

(4) data feeds that can be used to display with attribution to PSX Participants' MPIDs all Quotes and Displayed Orders on both the bid and offer side of the market for all price levels then within the PSX Market, and that disseminate such additional information about Quotes, Orders, and transactions within PSX as shall be reflected in the Equity Rules.

(b) The term "System Securities" shall mean any NMS stock, as defined in SEC Rule 600 except securities specifically excluded from trading via a list of excluded securities posted on www.nasdaqtrader.com.

(c) The term "PSX Participant" or "Participant" shall mean an entity that fulfills the obligations contained in General 2, Section 22 regarding participation in the System, and shall include:

(1) "Equities ECNs," which are member organizations that meet all of the requirements of Equity 2, Section 14, and that participate in the System with respect to one or more System Securities;

(2) "PSX Market Makers" or "Market Makers", member organizations that are registered as PSX Market Makers for purposes of participation in the System on a fully automated basis with respect to one or more System securities; and

(3) "Order Entry Firms," which are member organizations that are registered for the purposes of entering orders in System Securities into the System. This term shall also include any Electronic Communications Network or Alternative Trading System (as such terms are defined in Regulation NMS) that fails to meet all the requirements of Equity 2, Section 14.

(d) The term "Quote" means a single bid or offer quotation submitted to the System by a Market Maker or Equities ECN and designated for display (price and size) next to the Participant's MPID in the PSX Book. Quotes are entered in the form of Orders with Attribution (as defined in Equity 4, Rule 3301B). Accordingly, all Quotes are also Orders.

(e) The term "Order" means an instruction to trade a specified number of shares in a specified System Security submitted to PSX by a Participant. An "Order Type" is a standardized set of instructions associated with an Order that define how it will behave with respect to pricing, execution, and/or posting to the PSX Book when submitted to PSX. An "Order Attribute" is a further set of variable instructions that may be associated with an Order to further define how it will behave with respect to pricing, execution, and/or posting to the PSX Book when submitted to PSX. The available Order Types and Order Attributes, and the Order Attributes that may be associated with particular Order Types, are described in Rules 3301A and 3301B. One or more Order Attributes may be assigned to a single Order; provided, however, that if the use of multiple Order Attributes would provide contradictory instructions to an Order, the System will reject the Order or remove non-conforming Order Attributes.

(f) The term "ET" means Eastern Standard Time or Eastern Daylight Time, as applicable.

(g) The term "Market Hours" means the period of time beginning at 9:30 a.m. ET and ending at 4:00 p.m. ET (or such earlier time as may be designated by the Exchange on a day when PSX closes early). The term "System Hours" means the period of time beginning at 8:00 a.m. ET and ending at 5:00 p.m. ET (or such earlier time as may be designated by the Exchange on a day when PSX closes early). The term "Pre-Market Hours" means the period of time beginning at 8:00 a.m. ET and ending immediately prior to the commencement of Market Hours. The term "Post-Market Hours" means the period of time beginning immediately after the end of Market Hours and ending at 5:00 p.m. ET. The Exchange notes that in certain contexts, times cited in the Equity Rules may be approximate.

(h) The term "marketable" with respect to an Order to buy (sell) means that, at the time it is entered into the System, the Order is priced at the current Best Offer or higher (at the current Best Bid or lower).

(i) The term "market participant identifier" or "MPID" means a unique four-letter mnemonic assigned to each Participant in PSX. A Participant may have one or more than one MPID.

(j) The terms "Best Bid", "Best Offer", "National Best Bid and National Best Offer", "Protected Bid", "Protected Offer", "Protected Quotation" and "Intermarket Sweep Order" shall have the meanings assigned to them under Rule 600 under SEC Regulation NMS; provided, however, that the terms "Best Bid", "Best Offer", "Protected Bid", "Protected Offer", and "Protected Quotation" shall, unless otherwise stated, refer to the bid, offer, or quotation of a market center other than PSX. The term "NBBO" shall mean the "National Best Bid and National Best Offer".

(k) The term "minimum price increment" means $0.01 in the case of a System Security priced at $1 or more per share, and $0.0001 in the case of a System Security priced at less than $1 per share.

Adopted Jan. 2, 2021 (SR-Phlx-2021-04).