Pursuant to the provisions of Section 19(b)(1) of the Securities Exchange Act of 1934 (“Act” or “Exchange Act”) ^[1] and Rule 19b-4 thereunder,^[2] notice is hereby given that on May 27, 2026, 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.

I. Self-Regulatory Organization's Statement of the Terms of Substance of the Proposed Rule Change

The Exchange proposes to change the implementation date of the proposed change to provide origin code in the liquidity seeking event notification messages on the Administrative Information Subscriber (“AIS”) feed.

II. Self-Regulatory Organization's Statement of the Purpose of, and Statutory Basis for, the Proposed Rule Change

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.

A. Self-Regulatory Organization's Statement of the Purpose of, and Statutory Basis for, the Proposed Rule Change

1. Purpose

On September 11, 2025, the Exchange filed a proposal to amend the Administrative Information Subscriber market data feed (“AIS Feed”) to include origin code in the liquidity seeking event notification message.^[3] In its filing the Exchange proposed to announce the implementation date via Regulatory Circular. On February 20, 2026, the Exchange filed SR-MIAX-2026-10 ^[4] to extend the implementation date to Q4 of 2026 to allow Members ^[5] ample time to complete the necessary technical changes prior to the implementation of the change. The Exchange now proposes to change the implementation date to Q3 of 2026 as its Members have completed the necessary technical changes and are in a position to receive the new data element on the AIS feed.

The Exchange proposes to issue a Regulatory Circular notifying market participants of the actual date at least 30 days prior to implementation of this functionality.

2. Statutory Basis

The Exchange believes that its proposed rule change is consistent with Section 6(b) of the Act ^[6] in general, and furthers the objectives of Section 6(b)(5) of the Act ^[7] 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 regulating, clearing, settling, processing information with respect to, and facilitating transactions in, securities, to remove impediments to and perfect the mechanisms of a free and open market and a national market system and, in general, to protect investors and the public interest by allowing the Exchange and its Members to implement the proposed change.

B. Self-Regulatory Organization's Statement on Burden on Competition

The Exchange does not believe that the proposed rule change will result in any burden on competition that is not necessary or appropriate in furtherance of the purposes of the Act. The Exchange's proposal to implement the proposed functionality does not impose an undue burden on competition.

The Exchange does not believe that the proposed rule change will impose any burden on intramarket competition as subscribers to the AIS feed will receive the same information.

The Exchange does not believe that the proposed rule change will impose any burden on intermarket competition as the proposed change is a change in the implementation date of approved functionality. The Exchange does not believe that the proposed rule change will result in any burden on inter-market competition, but could serve to promote inter-market competition by possibly improving the number and quality of executions on the Exchange during liquidity seeking events which may improve competition for orders across all exchanges.

C. Self-Regulatory Organization's Statement on Comments on the Proposed Rule Change Received From Members, Participants, or Others

Written comments were neither solicited nor received.

III. Date of Effectiveness of the Proposed Rule Change and Timing for Commission Action

Because the foregoing proposed rule change does not: (i) significantly affect the protection of investors or the public interest; (ii) impose any significant burden on competition; and (iii) become operative for 30 days after the date of the filing, or such shorter time as the Commission may designate, it has become effective pursuant to Section 19(b)(3)(A) of the Act ^[8] and Rule 19b-4(f)(6) ^[9] thereunder.

At any time within 60 days of the filing of the proposed rule change, the Commission summarily may temporarily suspend such rule change if it appears to the Commission that such action is necessary or appropriate in the public interest, for the protection of investors, or otherwise in furtherance of the purposes of the Act.

IV. Solicitation of Comments

Interested persons are invited to submit written data, views and arguments concerning the foregoing, including whether the proposed rule change is consistent with the Act. Comments may be submitted by any of the following methods:

Electronic Comments

• Use the Commission's internet comment form (https://www.sec.gov/​rules/​sro.shtml); or
• Send an email torule-comments@sec.gov. Please include file number SR-MIAX-2026-23 on the subject line.

Paper Comments

• Send paper comments in triplicate to Secretary, Securities and Exchange Commission, 100 F Street NE, Washington, DC 20549-1090.

All submissions should refer to file number SR-MIAX-2026-23. This file number should be included on the subject line if email is used. To help the Commission process and review your comments more efficiently, please use only one method. The Commission will post all comments on the Commission's internet website ( https://www.sec.gov/​rules/​sro.shtml). Copies of the filing also will be available for inspection and copying at the principal office of the Exchange. Do not include personal identifiable information in submissions; you should submit only information that you wish to make available publicly. We may redact in part or withhold entirely from publication submitted material that is obscene or subject to copyright protection.

All submissions should refer to file number SR-MIAX-2026-23 and should be submitted on or before June 26, 2026.