CMECME Group

Please represent to us that you will revise future filings to include the geographic disclosures under ASC 280-10-50-41. Otherwise, tell us why they are not required. Exhibit 99.1, page General

We will provide the geographic disclosures in our future annual filings, as required by ASC 280-10-50-41. The following is an illustration of the proposed disclosure to be included within footnote 18, Segment Reporting, in our Form 10-K.

Material revenue and long-lived assets are defined as those which represent 10% or more of total revenues and long lived assets.

Rest of the answer

Revenue and long lived assets by country for the years ended December 31, 2025, 2024 and 2023 and as of December 31, 2025 and 2024 are set forth in the table below:

Revenues (b)

Long-lived Assets (c)

(in millions) 2025 2024 2023 2025 2024

United States $ xxx $ xxx $ xxx $ xxx $ xxx

United Kingdom (a) xxx xxx xxx xxx xxx

Other foreign countries xxx xxx xxx xxx xxx

Totals $ xxx $ xxx $ xxx $ xxx $ xxx

(a) United Kingdom includes Great Britain and Northern Ireland.

(b) Revenues are classified based upon the location of the customer.

(c) Long-lived assets represent property, plant and equipment, indefinite-lived intangible assets, amortizable intangible assets, and other investments included in other assets. See Note 5 for further information on property. See Note 6 for further information on goodwill and other intangible assets. See Note 17 for further information on investments included in other assets. These assets are reported in the country where they are primarily used.

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You reference Adjusted Operating Income and state that you recorded all-time record Adjusted Operating Income in the second quarter of 2025. We note that you do not quantify Adjusted Operating Income or include a reconciliation from a GAAP measure to this non-GAAP measure.

Rest of the question

Please either remove reference to this non- GAAP measure in future releases furnished on Forms 8-K, or advise otherwise as to why it is a meaningful and useful measure and include all of the disclosure requirements of Item 10(e) or Regulation S-K.

In future filings, the Company will include all applicable disclosure requirements of Item 10(e) of Regulation S-K for non-GAAP measures used. We believe that the presentation of non-GAAP Operating Income provides important supplemental information to management and investors about financial and business trends relating to the company’s financial condition and results of operations. We propose to include the following table within our future releases on Form 8-K to quantify and provide a reconciliation for GAAP to non-GAAP Operating Income.

CME Group Inc.

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and Subsidiaries

Adjusted Revenue, Operating Expense and Operating Income Reconciliation

(dollars in millions, except per share amounts; shares in thousands)

Quarter Ended

September 30,

Nine Months Ended

2025 2024 2025 2024

Total Revenues $

XXX

$

Real estate-related costs (credits)

Adjusted Revenues $

Expenses

Restructuring and severance

Deferred compensation(1)

Amortization of purchased intangibles

Strategic transaction-related costs

Foreign exchange transactions (gains) losses

Unrealized and realized (gains) losses on assets

Litigation matters or settlements

Adjusted Operating Expenses $

Operating Income $

Adjusted Operating Income $

1. Includes $X.X million and $X.X million for a change in our non-qualified deferred compensation liability in the third quarter and first nine months of 2025. This impact does not affect net income, because the compensation and benefits change has an equal and offsetting change in investment income.

We will also continue to include the reconciliation for GAAP to non-GAAP Net Income, Net Income Attributable to CME Group and Diluted EPS as shown in the following table.

Adjusted Net Income, Net Income Attributable to CME Group and Diluted EPS Reconciliation

Net Income $

Amortization of purchased intangibles(1)

Strategic transaction-related costs (credits)

Foreign exchange transaction (gains) losses

Unrealized and realized (gains) losses on investments

Income tax effect related to above

Other income tax items

Adjusted Net Income $

Adjusted Net Income Attributable to Common Shareholders of CME Group $

Earnings per Share Attributable to Common Shareholders of CME Group:

Basic $

Diluted

Adjusted Earnings per Share Attributable to Common Shareholders of CME Group:

Weighted Average Number of Common Shares:

Basic

Preferred shares(2)

1. Includes $X.X million and $X.X million of amortization of purchased intangibles (net of tax) at OSTTRA and $X.X million and $X.X million of amortization of purchased intangibles at S&P Dow Jones Indices LLC in the third quarter and first nine months of 2025. This is reported in Equity in net earnings of unconsolidated subsidiaries on the Consolidated Statements of Income.

2. Preferred shares have similar rights as common shares without voting rights.

In addition, the Company acknowledges:

•the Company is responsible for the adequacy and accuracy of the disclosures in the filing;

•Staff comments or changes to disclosures in response to Staff comments do not foreclose the Commission from taking any action with respect to the filing; and

•the Company may not assert Staff comments as a defense in any proceeding initiated by the Commission or any person under the federal securities laws in the United States.

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Please expand your discussion of the reasons you believe that your leadership structure is appropriate, addressing your specific characteristics or circumstances. In your discussion, please also address how the experience of your Lead Director is brought to bear in connection with your board’s role in risk oversight.

It is our belief that the Company’s disclosures in the Proxy Statement comply with all applicable rules and regulations, including Item 407(h) of Regulation S-K. Nonetheless, we will consider the Staff’s comments in due course as we evaluate the extent to which we voluntarily supplement our required disclosures in the future. Read in the reply ↗

Please expand upon the role that your Lead Director plays in the leadership of the board. For example, please enhance your disclosure to address whether or not your Lead Director may: • represent the board in communications with shareholders and other stakeholders; and • require board consideration of, and/or override your CEO on, any risk matters.

It is our belief that the Company’s disclosures in the Proxy Statement comply with all applicable rules and regulations, including Item 407(h) of Regulation S-K. Nonetheless, we will consider cmegroup.com CME GROUP CONFIDENTIAL the Staff’s comments in due course as we evaluate the extent to which we voluntarily supplement our required disclosures in the future. Read in the reply ↗

Please expand upon how your board administers its risk oversight function. For example, please disclose: • the specific risks over which the board elected to retain direct oversight responsibility and why oversight of those risks was not assigned to a board committee; • the timeframe over which you evaluate risks (e.g., short-term, intermediate-term, or long-term) and how you apply different oversight standards

Rest of the question

based upon the immediacy of the risk assessed; • whether you consult with outside advisors and experts to anticipate future threats and trends, and how often you re-assess your risk environment; • how the board interacts with management to address existing risks and identify significant emerging risks; • whether you have a Chief Compliance Officer and to whom this position reports; and • how your risk oversight process aligns with your disclosure controls and procedures.

It is our belief that the Company’s disclosures in the Proxy Statement comply with all applicable rules and regulations, including Item 407(h) of Regulation S-K. Nonetheless, we will consider the Staff’s comments in due course as we evaluate the extent to which we voluntarily supplement our required disclosures in the future. Read in the reply ↗

Business Combinations, page 62 1. We note that you completed the acquisition of NEX Group plc (NEX) on November 2, 2018 and, as disclosed in Exhibit 99.1 in your Form 8-K filed on November 8, 2018, that the pro forma 2017 annual revenues would be $4.3 billion giving effect to the acquisition, compared to your actual 2017 GAAP revenues of $3.6 billion.

Rest of the question

However, it is not clear where you have disclosed all information required by ASC 805 for this acquisition, such as the amounts of post-acquisition revenues and earnings or supplemental pro forma revenues and earnings required by ASC 805-10-50-2(h). In your future filings, please revise to disclose all information required by ASC 805-10-50 or tell us why you do not think it is required. 2. Please provide us with a summary of the income significance test pursuant to Rule 102(w) of Regulation S-X prepared in your determination of whether audited financial statements of NEX and full pro forma financial information should be provided pursuant to Rule 3-05 and Article 11 of Regulation S-X, respectively.

We propose to include the following disclosure within footnote 3 Business Combinations in our Form 10-K for the fiscal year ended December 31, 2019:

On November 2, 2018, the company completed its acquisition of NEX and its subsidiaries. For the two-month period ended December 31, 2018, NEX revenues and net losses, which include transaction-related costs, were $133.6 million and ($42.5) million respectively.

The following table presents pro forma information as if the acquisition of NEX had occurred on January 1, 2017.

Rest of the answer

This pro forma information combines the historical condensed consolidated results of operations of CME and NEX after giving effect to certain adjustments, including purchase accounting fair value adjustments, amortization of intangibles, stock-based compensation expense and acquisition costs, as well as the related income tax effects of those adjustments. The pro forma information does not necessarily reflect the results of operations that would have occurred had the company acquired NEX on January 1, 2017. Furthermore, cost savings and other business synergies related to the acquisition are not reflected in the pro forma amounts.

(in millions)

2018

2017

Total revenues

$

4,983.8

4,388.4

Net income

2,030.8

4,043.3

2. Please provide us with a summary of the income significance test pursuant to Rule 1-02(w) of Regulation S-X prepared in your determination of whether audited financial statements of NEX and full pro forma financial information should be provided pursuant to Rule 3-05 and Article 11 of Regulation S-X, respectively.

CME Response:

When an SEC registrant consummates or it is probable that it will consummate a significant business acquisition, SEC Regulation S-X Rule 3-05 (Rule 3-05) may require the filing of certain financial statements for the acquired or to be acquired business. For example, the registrant may be required to file a Form 8-K with financial statements for a significant acquiree. The determination as to whether an acquisition represents a “significant” business acquisition involves three tests:

A.

Asset Test: Compare CME’s share of NEX’s total assets to CME’s consolidated total assets.

B.

Investment Test: Compare total purchase price of NEX to CME’s total assets.

C.

Income Test: Compare CME’s equity in NEX’s income from continuing operations before taxes, extraordinary items and cumulative effect of a change in accounting principle to that of CME’s net income.

All three tests must be performed, and the one that results in the highest significance level will determine the financial statement periods that must be presented. The threshold begins at 20% for such financial statement requirements under Rule 3-05. The below table presents the results of the significance tests performed as of March 31, 2018 for NEX and December 31, 2017 for CME - the most recent pre-acquisition annual financial statements that are required to be filed with the SEC should generally be used for the significance tests.

Test

NEX

CME

Result

Asset Test

2,414.4

75,791.2

3%

Investment Test

5,600.0

7%

Income Test

174.6

2,526.3

As the NEX acquisition does not meet the 20% threshold noted above, the disclosure of audited financial statements and other pro forma information in accordance with SEC Regulation S-X Rule 3-05 (Rule 3-05) is not required.

In addition, at the Staff’s request, the Company acknowledges:

• the Company is responsible for the adequacy and accuracy of the disclosures in the filing;

Staff comments or changes to disclosures in response to Staff comments do not foreclose the Commission from taking any action with respect to the filing; and the Company may not assert Staff comments as a defense in any proceeding initiated by the Commission or any person under the federal securities laws in the United States.

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