Self-Regulatory Organizations; Miami International Securities Exchange, LLC; Notice of Filing and Immediate Effectiveness of a Proposed Rule Change To Amend the Administrative Information Subscriber Market Data Feed

<NOTICE> SECURITIES AND EXCHANGE COMMISSION <DEPDOC>[Release No. 34-104011; File No. SR-MIAX-2025-43]</DEPDOC> <SUBJECT>Self-Regulatory Organizations; Miami International Securities Exchange, LLC; Notice of Filing and Immediate Effectiveness of a Proposed Rule Change To Amend the Administrative Information Subscriber Market Data Feed</SUBJECT> <DATE>September 22, 2025.</DATE> Pursuant to the provisions of 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 September 11, 2025, Miami International Securities Exchange, LLC (“MIAX” or “Exchange”) filed with the Securities and Exchange Commission (“Commission”) a proposed rule change as described in Items I and II 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 the Administrative Information Subscriber market data feed to include the origin code on liquidity seeking event notifications. The text of the proposed rule change is available on the Exchange's website at <E T="03">https://www.miaxglobal.com/markets/us-options/all-options-exchanges/rule-filings</E> and at the Exchange's principal office. <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 proposes to amend the Administrative Information Subscriber market data feed (“AIS Feed”). The AIS Feed is a data feed that allows subscribers to receive real-time updates of the following information from the MIAX Options market (i) products traded on MIAX; (ii) trading status for MIAX and products trading on MIAX; and (iii) liquidity seeking event notifications. The Exchange now proposes to include the origin code in liquidity seeking event notifications. Currently the AIS Feed provides a Simple Liquidity Seeking Event Notification and a Complex Liquidity Seeking Event Notification. Both the Simple Liquidity Seeking Event Notification and the Complex Liquidity Seeking Event Notification message provide the type of liquidity seeking event in the Event Type field of each respective message. Specifically, for Simple Liquidity Seeking Event Notification messages, the following types of liquidity seeking events are identified in the following manner, a Liquidity Refresh Mechanism is denoted by an “L;” an Opening/Reopening Imbalance Mechanism is denoted by an “O;” a Route Mechanism is denoted by an “R;” a MIAX PRIME Paired order is denoted by a “P;” a Settlement Opening Imbalance Mechanism is denoted by an “S;” and a Liquidity Exposure Process is denoted by an “E.” Similarly, the Complex Liquidity Seeking Event Notification message provides the type of liquidity seeking event in the Event Type field. Specifically, a Complex Order Auction is denoted by a “C;” a cPRIME Auction is denoted by a “P;” and a Complex Liquidity Exposure Process Auction is denoted by an “E.”  <SU>3</SU> <FTREF/> <FTNT> <SU>3</SU>   <E T="03">See</E> Administrative Information Subscriber Feed, AIS Interface Specification, version 2.5, (8/1/2022) available online at <E T="03">https://www.miaxglobal.com/markets/us-options/miax-options/interface-specifications</E> . </FTNT> The Exchange now proposes to amend the Liquidity Seeking Event Notification and the Complex Liquidity Seeking Event Notification messages to adopt a new field name entitled “Origin.” The values for this new field will be mapped from the origin code provided in the FIX  <SU>4</SU> <FTREF/> New Order message and the FIX New Order Cross message for Simple Liquidity Seeking Event Notifications and Complex Liquidity Seeking Event Notifications respectively. Valid values for the Origin field will be: “0” for Priority Customer; “1” for Firm; “2” for Broker/Dealer; “4” for Market Maker; “5” for Non-Member Market Maker; “8” for Non-Priority Customer; and a blank space will signify “Not Applicable.” The Exchange also offers the MIAX Options Order Feed (MOR) which is a data feed that allows subscribers to receive real-time updates from the MIAX Options Market, with the origin code being provided in the Simple Order Message and Complex Order Message notifications. <SU>5</SU> <FTREF/> <FTNT> <SU>4</SU>  FIX is an acronym for Financial Information Exchange protocol. <E T="03">See www.fixtrading.org</E> . </FTNT> <FTNT> <SU>5</SU>   <E T="03">See</E> MIAX Order Feed (MOR) Interface Specification, version 2.5b, (5/17/2022) available online at <E T="03">https://www.miaxglobal.com/markets/us-options/miax-options/interface-specifications</E> . </FTNT> <HD SOURCE="HD3">Implementation</HD> There will be technology changes associated with this rule proposal, therefore the Exchange proposes to announce the implementation date of the proposal in a Regulatory Circular to be published no later than 90 days after the publication of the approval order in the <E T="04">Federal Register</E> . The implementation date will be no later than 90 days following publication of the Regulatory Circular announcing publication of the approval order in the <E T="04">Federal Register</E> . <HD SOURCE="HD3">2. Statutory Basis</HD> The Exchange believes that its proposed rule change is consistent with Section 6(b) of the Act, <SU>6</SU> <FTREF/> in general, and furthers the objectives of Section 6(b)(5) of the Act  <SU>7</SU> <FTREF/> in particular, in that it is designed to prevent fraudulent and manipulative acts and practices, to promote just and equitable principles of trade, to foster cooperation and coordination with persons engaged in facilitating transactions in securities, to remove impediments to and perfect the mechanism of a free and open market and a national market system, and, in general, to protect investors and the public interest. The Exchange believes this proposal is consistent with Section 6(b)(5) of the Act because it protects investors and the public interest and promotes just and equitable principles of trade by providing investors with additional information by which to make trading decisions. <FTNT> <SU>6</SU>  15 U.S.C. 78f(b). </FTNT> <FTNT> <SU>7</SU>  15 U.S.C. 78f(b)(5). </FTNT> The proposed changes to the market data product are designed to increase the efficient use of the AIS Feed and to promote just and equitable principles of trade, foster cooperation and coordination with persons engaged in facilitating transactions in securities, removes impediments to and perfect the mechanisms of a free and open market and a national market system. The Exchange believes that the proposed changes will enhance the quality and usefulness of the AIS Feed to the benefit of all market participants by providing additional information related to liquidity seeking events which will help participants make better informed decisions regarding these events. The AIS Feed is designed to promote just and equitable principles of trade by providing all subscribers with real-time updates of products trading on MIAX, the trading status of such products, and liquidity seeking event notifications. The proposed change to the AIS Feed will further perfect the mechanisms of a free and open market and a national market system by making the MIAX market more transparent and accessible to market participants. The Exchange also believes that its proposal is consistent with Section 6(b) of the Act  <SU>8</SU> <FTREF/> in general, and further the objectives of Section 6(b)(4) of the Act  <SU>9</SU> <FTREF/> in particular, in that it is an equitable allocation of reasonable dues, fees, and other charges among its members and issuers and other persons using its facilities. Subscribers to the Administrative Information Subscriber data feed are changed a monthly fee. <SU>10</SU> <FTREF/> The Exchange believes that it is reasonable to leave the fee charged for the AIS Feed unchanged as the AIS Feed currently contains liquidity seeking event notifications and the Exchange's proposal seeks only to enhance the data provided in liquidity seeking event messages. Therefore, the Exchange does not believe that the proposed change requires a change to its Fee Schedule. <FTNT> <SU>8</SU>  15 U.S.C. 78f(b). </FTNT> <FTNT> <SU>9</SU>  15 U.S.C. 78f(b)(4). </FTNT> <FTNT> <SU>10</SU>   <E T="03">See</E> Section 6)b) of the Exchange's Fee Schedule available online at <E T="03">https://www.miaxglobal.com/markets/us-options/miax-options/fees</E> . </FTNT> Further, the Exchange believes that its proposal is fair and not unreasonably discriminatory because it applies equally to all subscribers of the AIS Feed and all subscribers of the AIS Feed receive the same data. The Exchange believes that its proposal provides for the equitable allocation of reasonable dues, fees and other charges among its Members and other persons using its facilities and is not designed to unfairly discriminate between customers, issuers, brokers, or dealer ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 15k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━