Notice2025-20390
Self-Regulatory Organizations; Cboe BYX Exchange, Inc.; Notice of Filing and Immediate Effectiveness of a Proposed Rule Change To Amend Exchange Rule 11.10, Units of Trading, To Conform With the Amendment to the Definition of Round Lot Under Rule 600 of Regulation NMS
Primary source
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Published
November 20, 2025
Issuing agencies
Securities and Exchange Commission
Full Text
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<title>Federal Register, Volume 90 Issue 222 (Thursday, November 20, 2025)</title>
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[Federal Register Volume 90, Number 222 (Thursday, November 20, 2025)]
[Notices]
[Pages 52478-52480]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2025-20390]
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SECURITIES AND EXCHANGE COMMISSION
[Release No. 34-104191; File No. SR-CboeBYX-2025-030]
Self-Regulatory Organizations; Cboe BYX Exchange, Inc.; Notice of
Filing and Immediate Effectiveness of a Proposed Rule Change To Amend
Exchange Rule 11.10, Units of Trading, To Conform With the Amendment to
the Definition of Round Lot Under Rule 600 of Regulation NMS
November 17, 2025.
Pursuant to Section 19(b)(1) of the Securities Exchange Act of 1934
(``Act''),\1\ and Rule 19b-4 thereunder,\2\ notice is hereby given that
on September 30, 2025, Cboe BYX Exchange, Inc. (``Exchange'' or
``BYX'') filed with the Securities and Exchange Commission
(``Commission'') the proposed rule change as described in Items I, II,
and III below, which Items have been prepared by the Exchange. The
Exchange filed the proposal as a ``non-controversial'' proposed rule
change pursuant to Section 19(b)(3)(A)(iii) of the Act \3\ and Rule
19b-4(f)(6) thereunder.\4\ The Commission is publishing this notice to
solicit comments on the proposed rule change from interested persons.
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\1\ 15 U.S.C. 78s(b)(1).
\2\ 17 CFR 240.19b-4.
\3\ 15 U.S.C. 78s(b)(3)(A)(iii).
\4\ 17 CFR 240.19b-4(f)(6).
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I. Self-Regulatory Organization's Statement of the Terms of Substance
of the Proposed Rule Change
Cboe BYX Exchange, Inc. (``BYX'' or the ``Exchange'') is filing
with the Securities and Exchange Commission (the ``Commission'') a
proposed rule change to amend Exchange Rule 11.10, Units of Trading, to
conform with the amendment to the definition of round lot under Rule
600 of Regulation NMS recently approved by the Commission.\5\ The
Exchange also proposes to make a conforming, non-substantive change to
Exchange Rule 11.8(d)(1), Continuous, Two-Sided Quote Obligation. The
text of the proposed rule changes is in Exhibit 5.
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\5\ See Securities Exchange Act Release No. 101070 (September
18, 2024), 89 FR 81620 (October 8, 2024) (S7-30-22).
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The text of the proposed rule change is also available on the
Commission's website (<a href="https://www.sec.gov/rules/sro.shtml">https://www.sec.gov/rules/sro.shtml</a>), the
Exchange's website (<a href="https://www.cboe.com/us/equities/regulation/rule_filings/bzx/">https://www.cboe.com/us/equities/regulation/rule_filings/bzx/</a>), and at the principal office of the Exchange.
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
The Exchange proposes to amend Exchange Rule 11.10, Units of
Trading, to conform with the definition of round lot under Rule 600 of
the Regulation NMS that is to be implemented in November 2025.\6\ The
Exchange also proposes to make a conforming, non-substantive change to
Exchange Rule 11.8(d)(1), Continuous, Two-Sided Quote Obligation.
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\6\ See supra note 5.
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In 2020, the Commission adopted amendments to Regulation NMS to
modernize the NMS information provided within the national market
system for the benefit of market participants and to better achieve
Section 11A's goals of assuring ``the availability to brokers, dealers,
and investors of information with respect to quotations for and
transactions in securities that is prompt, accurate, reliable, and
fair'' (``MDI Rules'').\7\ These changes included an amendment to Rule
600 of Regulation NMS to include a definition of ``round lot'' that
assigns each NMS stock to a round lot size based on the stock's average
closing price.\8\ Prior to this change, a ``round lot'' was not defined
in the Act or Regulation NMS. The definition of a ``round lot'' was
included in the rules of the individual exchanges, including Exchange
Rule 11.10, which defined a ``round lot'' as one hundred shares.
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\7\ See Securities Exchange Act Release No. 90610 (December 9,
2020), 86 FR 18596 (April 9, 2021) (``MDI Adopting Release'').
\8\ See id.
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On September 18, 2024, the Commission accelerated the
implementation of the round lot definition.\9\ The Commission also
revised the round lot definition as set forth below.\10\ Rule
600(b)(93) of Regulation NMS, as adopted by the MDI Rules and as
amended in 2024,\11\ defines a round lot for NMS stocks \12\ that have
an average closing price on the primary listing exchange during the
prior Evaluation Period \13\ of: ``(1) $250.00 or less per share as 100
shares; (2) $250.01 to $1,000.00 per share as 40 shares; (3) $1,000.01
to $10,000.00 per share as 10 shares; and (4) $10,000.01 or more per
share as 1 share.'' \14\ For any security that becomes an NMS Stock
during an operative period, as described in Rule 600(b)(93)(iv),\15\ a
round lot is 100 shares. Adjustments to the round lot size for a
security will occur on a
[[Page 52479]]
semiannual basis and the calculation of the average closing price on
the primary listing exchange will be based on a one-month Evaluation
Period.\16\ The revised definition of round lot is to be implemented on
November 3, 2025, the first business day of November 2025.\17\ The
Exchange now proposes to amend Exchange Rule 11.10, Units of Trading,
to conform with the definition of round lot under Rule 600 of the
Regulation NMS.
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\9\ See supra note 5.
\10\ See supra note 5.
\11\ See supra note 5.
\12\ ``NMS stock'' is defined under Regulation NMS as any NMS
security other than an option. 17 CFR 242.600(b)(65).
\13\ Rule 600(b)(93)(iii) of Regulation NMS defines the
Evaluation Period as ``(A) all trading days in March for the round
lot assigned on the first business day in May and (B) all trading
days in September for the round lot assigned on the first business
day of November during which the average closing price of an NMS
stock on the primary listing exchange shall be measured by the
primary listing exchange to determine the round lot for each NMS
stock.''
\14\ See supra note 5.
\15\ Pursuant to Rule 600(b)(93)(iv) of Regulation NMS the round
lot assigned under the section ``shall be operative on (A) the first
business day of May for the March Evaluation Period and continue
through the last business day of October of the calendar year, and
(B) the first business day of November for the September Evaluation
Period and continue through the last business day of April of the
next calendar year.''
\16\ See supra note 5.
\17\ See supra note 5.
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Exchange Rule 11.10 currently provides that ``[o]ne hundred (100)
shares shall constitute a `round lot,' any amount less than 100 shares
shall constitute an `odd lot,' and any amount greater than 100 shares
that is not a multiple of a round lot shall constitute a `mixed lot.'''
The Exchange now proposes to amend the sentence above to explicitly
refer to the definition of a ``round lot'' under Rule 600 of Regulation
NMS and adjust the definition of ``odd lot'' and ``mixed lot'' to
conform with the newly adopted definition of ``round lot.'' As a
result, the above sentence will be deleted and replaced with the
following: ``[a] `round lot' for each NMS Stock shall be the size
assigned by the primary listing market pursuant to Rule 600 of
Regulation NMS under the Exchange Act. An `odd lot' shall be any amount
less than a round lot and a `mixed lot' shall be any amount greater
than a round lot that is not an integer multiple of a round lot.''
Again, the Exchange proposes this change solely to conform the
Exchange's definition of ``round lot'' under Exchange Rule 11.10 to the
new definition of round lot under Rule 600 of Regulation NMS.
The Exchange also proposes to make a conforming, non-substantive
change to Exchange Rule 11.8(d)(1), Continuous, Two-Sided Quote
Obligation, to conform to with the Exchange's definition of round lot.
Exchange Rule 11.8(d)(1) currently provides that ``[u]nless otherwise
designated, a `normal unit of trading' shall be 100 shares.'' The
Exchange proposes to replace the aforementioned sentence with a
sentence that conforms to the newly adopted definition of round lot in
the Exchange's Rulebook. As a result, the above sentence will be
removed and replaced with the following: ``[u]nless otherwise
designated, a `normal unit of trading' shall be a round lot as defined
in Exchange Rule 11.10.''
The purpose of these changes is to provide greater clarity to
Exchange Members \18\ and the public regarding the Exchange's Rulebook.
The Exchange does not propose any additional rule changes. The proposed
rule changes will be implemented on November 3, 2025, the same date as
the revised definition of round lot under Regulation NMS is to be
implemented.
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\18\ See Exchange Rule 1.5(n). A ``Member'' is defined as ``any
registered broker or dealer that has been admitted to membership in
the Exchange.''
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2. Statutory Basis
The Exchange believes the proposed rule changes are consistent with
the Securities Exchange Act of 1934 (the ``Act'') and the rules and
regulations thereunder applicable to the Exchange and, in particular,
the requirements of Section 6(b) of the Act.\19\ Specifically, the
Exchange believes the proposed rules change are consistent with the
Section 6(b)(5) \20\ requirements that the rules of an exchange be
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
mechanism of a free and open market and a national market system, and,
in general, to protect investors and the public interest. Additionally,
the Exchange believes the proposed rule changes are consistent with the
Section 6(b)(5) \21\ requirement that the rules of an exchange not be
designed to permit unfair discrimination between customers, issuers,
brokers, or dealers.
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\19\ 15 U.S.C. 78f(b).
\20\ 15 U.S.C. 78f(b)(5).
\21\ Id.
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The Exchange proposes to amend Exchange Rule 11.10, Units of
Trading, to conform with the definition of round lot under Rule 600 of
the Regulation NMS that is to be implemented in November 2025.\22\ This
change is being proposed solely to conform the Exchange's definition of
``round lot'' under Exchange Rule 11.10 to the new definition of round
lot under Rule 600 of Regulation NMS. The Exchange also proposes to
make a conforming, non-substantive change to Exchange Rule 11.8(d)(1),
Continuous, Two-Sided Quote Obligation, which is limited to conforming
the Rule to the Exchange's definition of round lot.
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\22\ See supra note 5.
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The proposed changes do not amend the operation of the affected
rules. The proposed rule changes would reduce potential investor and
market participant confusion and therefore remove impediments to and
perfect the mechanism of a free and open market and a national market
system by ensuring that the Exchange's rules properly reflect the
requirements of Rule 600 of Regulation NMS. The Exchange also believes
that the proposed rule changes would remove impediments to and perfect
the mechanism of a free and open market by ensuring that persons
subject to the Exchange's jurisdiction, regulators, and the investing
public can more easily navigate and understand the Exchange's rules.
The proposed rule changes would not be inconsistent with the public
interest or the protection of investors because investors will not be
harmed and, in fact, would benefit from the increased transparency and
clarity, thereby reducing potential confusion.
B. Self-Regulatory Organization's Statement on Burden on Competition
The Exchange believes the proposed rule changes do not impose any
burden on intramarket or intermarket competition that is not necessary
or appropriate in furtherance of the purposes of the Act. The proposed
rule change to amend the definition of round lot is not intended to
address competitive issues; rather, the proposed change is concerned
solely with amending the Exchange's Rule to conform with the definition
of round lot under Rule 600 of the Regulation NMS. The proposed rule
change to amend Exchange Rule 11.8(d)(1) to conform to with the
Exchange's definition of round lot is conforming and non-substantive in
nature and not intended to address competitive issues.
C. Self-Regulatory Organization's Statement on Comments on the Proposed
Rule Change Received From Members, Participants, or Others
The Exchange neither solicited nor received comments on the
proposed rule change.
III. Date of Effectiveness of the Proposed Rule Change and Timing for
Commission Action
Because the foregoing proposed rule change does not:
A. significantly affect the protection of investors or the public
interest;
B. impose any significant burden on competition; and
C. become operative for 30 days from the date on which it was
filed, or such shorter time as the Commission may designate, it has
become effective pursuant to Section 19(b)(3)(A) of the
[[Page 52480]]
Act \23\ and Rule 19b-4(f)(6) \24\ thereunder.
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\23\ 15 U.S.C. 78s(b)(3)(A).
\24\ 17 CFR 240.19b-4(f)(6). In addition, Rule 19b-4(f)(6)
requires a self-regulatory organization to give the Commission
written notice of its intent to file the proposed rule change, along
with a brief description and text of the proposed rule change, at
least five business days prior to the date of filing of the proposed
rule change, or such shorter time as designated by the Commission.
The Exchange has satisfied this requirement.
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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. If the Commission
takes such action, the Commission will institute proceedings to
determine whether the proposed rule change should be approved or
disapproved.
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
<bullet> Use the Commission's internet comment form (<a href="https://www.sec.gov/rules/sro.shtml">https://www.sec.gov/rules/sro.shtml</a>); or
<bullet> Send an email to <a href="/cdn-cgi/l/email-protection#a4d6d1c8c189c7cbc9c9c1cad0d7e4d7c1c78ac3cbd2"><span class="__cf_email__" data-cfemail="96e4e3faf3bbf5f9fbfbf3f8e2e5d6e5f3f5b8f1f9e0">[email protected]</span></a>. Please include
file number SR-CboeBYX-2025-030 on the subject line.
Paper Comments
<bullet> 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-CboeBYX-2025-030. 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 (<a href="https://www.sec.gov/rules/sro.shtml">https://www.sec.gov/rules/sro.shtml</a>). Copies of the filing 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-CboeBYX-2025-030 and should be submitted
on or before December 11, 2025.
For the Commission, by the Division of Trading and Markets,
pursuant to delegated authority.\25\
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\25\ 17 CFR 200.30-3(a)(12).
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Sherry R. Haywood,
Assistant Secretary.
[FR Doc. 2025-20390 Filed 11-19-25; 8:45 am]
BILLING CODE 8011-01-P
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