Self-Regulatory Organizations; Nasdaq PHLX LLC; Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend PHLX Equity 4, Rule 3301A(b) To Specify That the “Time-in-Force” Order Attribute of “Immediate-or-Cancel” Is Not Available to Post-Only Orders or Midpoint Peg Post-Only Orders Entered Through the CORE FIX Protocol, and To Correct a Clerical Error Regarding the Availability of the Trade Now Order Attribute for Midpoint Peg Post-Only Orders

<NOTICE> SECURITIES AND EXCHANGE COMMISSION <DEPDOC>[Release No. 34-104297; File No. SR-PHLX-2025-63]</DEPDOC> <SUBJECT>Self-Regulatory Organizations; Nasdaq PHLX LLC; Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend PHLX Equity 4, Rule 3301A(b) To Specify That the “Time-in-Force” Order Attribute of “Immediate-or-Cancel” Is Not Available to Post-Only Orders or Midpoint Peg Post-Only Orders Entered Through the CORE FIX Protocol, and To Correct a Clerical Error Regarding the Availability of the Trade Now Order Attribute for Midpoint Peg Post-Only Orders</SUBJECT> <DATE>December 3, 2025.</DATE> Pursuant to Section 19(b)(1) of the Securities Exchange Act of 1934 (“Act”), <SU>1</SU> <FTREF/> and Rule 19b-4 thereunder, <SU>2</SU> <FTREF/> notice is hereby given that on November 24, 2025, Nasdaq PHLX LLC (“PHLX” or “Exchange”) filed with the Securities and Exchange Commission (“SEC” or “Commission”) the proposed rule change as described in Items I, II, and III, below, which Items have been prepared by the Exchange. The Commission is publishing this notice to solicit comments on the proposed rule change from interested persons. <FTNT> <SU>1</SU>  15 U.S.C. 78s(b)(1). </FTNT> <FTNT> <SU>2</SU>  17 CFR 240.19b-4. </FTNT> <HD SOURCE="HD1">I. Self-Regulatory Organization's Statement of the Terms of Substance of the Proposed Rule Change</HD> The Exchange proposes to amend PHLX Equity 4, Rule 3301A(b) to specify that the “Time-in-Force” Order Attribute of “Immediate-or-Cancel” is not available to Post-Only Orders or Midpoint Peg Post-Only Orders entered through the CORE FIX protocol, and to correct a clerical error regarding the availability of the Trade Now Order Attribute for Midpoint Peg Post-Only Orders. The text of the proposed rule change is available on the Exchange's website at <E T="03">https://listingcenter.nasdaq.com/rulebook/PHLX/rulefilings,</E> and at the principal office of the Exchange. <HD SOURCE="HD1">II. Self-Regulatory Organization's Statement of the Purpose of, and Statutory Basis for, the Proposed Rule Change</HD> In its filing with the Commission, the Exchange included statements concerning the purpose of and basis for the proposed rule change and discussed any comments it received on the proposed rule change. The text of these statements may be examined at the places specified in Item IV below. The Exchange has prepared summaries, set forth in sections A, B, and C below, of the most significant aspects of such statements. <HD SOURCE="HD2">A. Self-Regulatory Organization's Statement of the Purpose of, and Statutory Basis for, the Proposed Rule Change</HD> <HD SOURCE="HD3">1. Purpose</HD> The Exchange's rules provide participants five Order  <SU>3</SU> <FTREF/> entry protocols: and CORE FIX. <SU>8</SU> <FTREF/> Due to differences in the technical designs and capabilities of these protocols, they offer market participants different functionalities and experiences with respect to order handling. That is, order handling behaviors on the Exchange vary, in certain circumstances, depending upon the particular protocol that a Participant chooses to utilize to enter its Orders in connection with particular Order Types  <SU>9</SU> <FTREF/> and Order Attributes. <SU>10</SU> <FTREF/> <FTNT> <SU>3</SU>  The term “Order” means an instruction to trade a specified number of shares in a specified NMS stock submitted to “PSX” or “System” by a participant. <E T="03">See</E> PHLX Equity 1, Section 1(e). “PSX” or “System” is the automated system for order execution and trade reporting owned and operated by the Exchange. <E T="03">See</E> PHLX Equity 1, Section 1(a). </FTNT> <FTNT> <SU>4</SU>  The OUCH Order entry protocol is a proprietary protocol that allows subscribers to quickly enter orders into the System and receive executions. OUCH accepts limit Orders from members, and if there are matching Orders, they will execute. Non-matching Orders are added to the Limit Order Book, a database of available limit Orders, where they are matched in price-time priority. OUCH only provides a method for members to send Orders and receive status updates on those Orders. <E T="03">See https://www.nasdaqtrader.com/Trader.aspx?id=OUCH.</E> </FTNT> <FTNT> <SU>5</SU>  RASH (Routing and Special Handling) is a proprietary protocol that allows participants to enter Orders, cancel existing Orders and receive executions while providing smart order routing and special handling features. RASH also allows participants to use advanced functionality, including discretion, random reserve, pegging and routing. <E T="03">See https://www.nasdaqtrader.com/Trader.aspx?id=RASH.</E> </FTNT> <FTNT> <SU>6</SU>  FIX is a vendor-neutral standard message protocol that defines an electronic message exchange for communicating securities transactions between two parties. The Exchange's FIX implementation acts like a router, converting incoming FIX messages into OUCH messages and back again. <E T="03">See https://www.nasdaqtrader.com/Trader.aspx?id=FIX</E> and <E T="03">https://www.nasdaqtrader.com/content/ProductsServices/Trading/Protocols_quickref.pdf.</E> </FTNT> <FTNT> <SU>7</SU>  FIX Lite or “FLITE” is an Order entry protocol based on a subset of FIX. <E T="03">See https://www.nasdaqtrader.com/Trader.aspx?id=FLITE</E> and <E T="03">https://www.nasdaqtrader.com/content/ProductsServices/Trading/Protocols_quickref.pdf.</E> </FTNT> <FTNT> <SU>8</SU>  CORE FIX is a proprietary order entry protocol that will allow participants to code for FIX, while enjoying the faster direct access to the Exchange that is offered by OUCH. The CORE FIX order entry protocol became effective on PHLX on September 23, 2025, but it has not yet become operative on the Exchange. <E T="03">See https://www.nasdaqtrader.com/TraderNews.aspx?id=ETA2025-57</E> <E T="03">and</E> Securities Exchange Act Release No. 104020 (Sept. 23, 2025), 90 FR 46446 (Sept. 26, 2025) (File No. SR-PHLX-2025-46) (Self-Regulatory Organizations; Nasdaq PHLX LLC; Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend PHLX Equity 4, Rules 3100, 3301A, 3301B, and 3307 To Add the CORE FIX Order Entry Protocol) (“2025 Filing”). </FTNT> <FTNT> <SU>9</SU>  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 the System. <E T="03">See</E> PHLX Equity 1, Section 1(e). The “PSX Book” is a montage for quotes and orders that collects and ranks all quotes and orders submitted by participants. <E T="03">See</E> PHLX Equity 1, Section 1(a)(1). </FTNT> <FTNT> <SU>10</SU>  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. <E T="03">See</E> PHLX Equity 1, Section 1(e). </FTNT> Currently, PHLX Equity 4, Rule 3301A(b)(4)(C) and Rule 3301A(b)(6)(C) specify that a Post-Only Order and a Midpoint Peg Post-Only Order, respectively, with a Time-in-Force of Immediate-or-Cancel (“IOC”)  <SU>11</SU> <FTREF/> may not be entered through RASH or FIX. The Exchange proposes to amend these rules to specify that these exclusions also apply to orders entered through the CORE FIX protocol. In other words, a Post-Only Order or a Midpoint Peg Post-Only Order with a Time-in-Force of IOC may not be entered through RASH, FIX, or CORE FIX. <FTNT> <SU>11</SU>  An order with an IOC Order Attribute is to be executed in whole or in part upon receipt. Any portion not so executed is cancelled. </FTNT> Additionally, the Exchange wishes to correct a clerical error in PHLX Equity 4, Rule 3301A(b)(6)(C) regarding the availability of the Trade Now Order Attribute for Midpoint Peg Post-Only Orders. In 2024 the Exchange removed the Trade Now Order Attribute from the list of Order Attributes available for Midpoint Peg Post-Only Orders. <SU>12</SU> <FTREF/> However, the Exchange mistakenly did not make this change to its rulebook on the Exchange's website. Therefore, earlier this year, when the Exchange modified this same rule as part of its filing to add the CORE FIX order entry protocol to the Exchange, the Exchange mistakenly modified this deleted rule text to add CORE FIX to the list of order entry protocols through which the Trade Now Order Attribute is available for Midpoint Peg Post Only Orders. <SU>13</SU> <FTREF/> The Exchange proposes to correct this clerical error by again removing the Trade Now Order Attribute from the list of order attributes available for Midpoint Peg Post-Only Orders. <FTNT> <SU>12</SU>   <E T="03">See</E> Securities Exchange Act Release No. 100061 (May 3, 2024), 89 FR 39671 (May 9, 2024) (File No. SR-PHLX-2024-22) (Self-Regulatory Organizations; Nasdaq PHLX LLC; Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend the Trade Now Order Attribute, at Equity 4, Rule 3301B and Rule 3301A) (“2024 Filing”). </FTNT> <FTNT> <SU>13</SU>   <E T="03">See</E> 2025 Filing. </FTNT> The Exchange will announce the implementation date of the new CORE FIX Order Entry Protocol, including the functionality described in this filing, in an Equity Trader Alert at least 30 days prior to implementation. At present, the Exchange expects that the new CORE FIX functionality will be ready for implementation in the first quarter of 2026, although that time frame is subject to change. The Exchange will remove from its rulebook the incorrect language in PHLX Equity 4, Rule 3301A(b)(6)(C) regarding the availability of the Trade Now Order Attribute for Midpoint Peg Post-Only Orders 30 days after the date of this filing. <HD SOURCE="HD3">2. Statutory Basis</HD> The Exch ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 20k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━