Annual Report of Employee Stock Purchase/Savings Plan Form 11 K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

___________________

FORM 11-K

ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

FOR THE FISCAL YEAR ENDED DECEMBER 31, 2023

____________________

A. Full title of the plan and the address of the plan, if different from that of the issuer named below:

OMNICOM GROUP RETIREMENT SAVINGS PLAN

B. Name of issuer of the securities held pursuant to the plan and the address of its principal executive office:

OMNICOM GROUP INC.

280 Park Avenue

New York, NY 10017

OMNICOM GROUP RETIREMENT SAVINGS PLAN

ANNUAL REPORT ON FORM 11-K FOR THE YEAR ENDED DECEMBER 31, 2023

TABLE OF CONTENTS

Page
REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM:
PKF O'Connor Davies, LLP	1
FINANCIAL STATEMENTS:
Statements of Net Assets Available for Benefits as of December 31, 2023 and 2022	2
Statements of Changes in Net Assets Available for Benefits for the Years Ended December 31, 2023 and 2022	3
Notes to Financial Statements	4
SUPPLEMENTAL SCHEDULE:
Schedule H, Line 4i - Schedule of Assets (Held at End of Year) at December 31, 2023	10
SIGNATURE	11
EXHIBIT 23:
Consent of Independent Registered Public Accounting Firm	12

i

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Plan Administrator and Participants

Omnicom Group Retirement Savings Plan

New York, New York

Opinion on the Financial Statements

We have audited the accompanying statements of net assets available for benefits of the Omnicom Group Retirement Savings Plan (the Plan) as of December 31, 2023 and 2022, and the related statements of changes in net assets available for benefits for the years ended December 31, 2023 and 2022, and the related notes (collectively referred to as the financial statements). In our opinion, the financial statements present fairly, in all material respects, the net assets available for benefits of the Plan as of December 31, 2023 and 2022, and the changes in net assets available for benefits for the years ended December 31, 2023 and 2022, in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Plan's management. Our responsibility is to express an opinion on the Plan's financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Plan in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Plan is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting, but not for the purpose of expressing an opinion on the effectiveness of the Plan's internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by the Plan's management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Supplemental Information

The supplemental information contained in Schedule H, Line 4i - Schedule of Assets (Held at End of Year) at December 31, 2023 has been subjected to audit procedures performed in conjunction with the audit of the Plan's financial statements. The supplemental information is the responsibility of the Plan's management. Our audit procedures included determining whether the supplemental information reconciles to the financial statements or the underlying accounting and other records, as applicable, and performing procedures to test the completeness and accuracy of the information presented in the supplemental information. In forming our opinion on the supplemental information, we evaluated whether the supplemental information, including its form and content, is presented in conformity with the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. In our opinion, the supplemental information is fairly stated, in all material respects, in relation to the financial statements as a whole.

/s/ PKF O'Connor Davies, LLP

We have served as the Plan's auditor since 2009.

Harrison, New York

June 27, 2024

PCAOB ID No. 127

1

OMNICOM GROUP RETIREMENT SAVINGS PLAN

STATEMENTS OF NET ASSETS AVAILABLE FOR BENEFITS

December 31,
2023	2022
Assets:
Investments, at fair value:
Mutual Funds	$	995,415,364	$	1,021,167,687
Common/Collective Trusts	2,576,560,728	1,934,969,689
Company Stock	108,884,573	109,063,044
3,680,860,665	3,065,200,420
Investments, at contract value	223,600,010	255,938,147
Total Investments	3,904,460,675	3,321,138,567
Receivables:
Employer contributions	51,800,000	48,641,000
Notes receivable from participants	21,522,758	20,518,458
Accrued interest and dividends	881,892	938,004
Due from broker for investments sold	13,351	228,166
Total Receivables	74,218,001	70,325,628
Total Assets	3,978,678,676	3,391,464,195
Liabilities:
Accrued expenses and other	597,812	667,712
Due to broker for investments purchased	97,711	360,435
Total Liabilities	695,523	1,028,147
Net Assets Available for Benefits	$	3,977,983,153	$	3,390,436,048

See accompanying notes to financial statements.

2

OMNICOM GROUP RETIREMENT SAVINGS PLAN

STATEMENTS OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS

Year Ended December 31,
2023	2022
Additions:
Contributions:
Employer	$	51,909,733	$	48,674,146
Participants	202,697,066	188,751,130
Rollovers	26,894,978	32,912,882
281,501,777	270,338,158
Dividend and interest income	42,892,889	61,831,194
Net appreciation in fair value of investments	609,100,341	-
Total Additions	933,495,007	332,169,352
Deductions:
Benefits paid	349,079,963	288,550,690
Administrative expenses	1,896,452	1,675,044
Net depreciation in fair value of investments	-	804,413,906
Total Deductions	350,976,415	1,094,639,640
Net increase (decrease)	582,518,592	(762,470,288)
Assets transferred into Plan	5,028,513	2,253,259
Net assets available for benefits:
Beginning of year	3,390,436,048	4,150,653,077
End of year	$	3,977,983,153	$	3,390,436,048

See accompanying notes to financial statements.

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OMNICOM GROUP RETIREMENT SAVINGS PLAN

NOTES TO FINANCIAL STATEMENTS

1. Description of Plan

The following brief description of the Omnicom Group Retirement Savings Plan, or the Plan, provides only general information. Participants should refer to the Summary Plan Description, or SPD, or the Plan document for a more complete description of the Plan's provisions. In the event of any conflict between the SPD and the Plan document, the Plan document will control.

General

The Plan is a defined contribution retirement plan covering all eligible employees of participating companies of Omnicom Group Inc., or the Company, and the Company is the sponsor of the Plan. The Plan is subject to the provisions of the Employee Retirement Income Security Act of 1974, as amended, or ERISA, and to the provisions of the Internal Revenue Code of 1986, as amended, or the Code, as it pertains to plans intended to qualify under Section 401(a) of the Code. The Administrative Committee, or the Committee, comprised of persons appointed by the Company's Board of Directors, or its delegate, administers the Plan and is responsible for resolving all questions that may arise under the Plan. The Plan's assets are held in trust with Fidelity Management Trust Company, or the Trustee, and an affiliate of the Trustee performs the recordkeeping services for the Plan.

Eligibility and Plan Entry Dates

For the 401(k) and matching contribution features of the Plan, eligible employees of participating companies can enroll in the Plan as soon as administratively practicable following employment. For the profit sharing feature of the Plan, eligible employees of participating companies were generally eligible twelve months after their date of hire and were enrolled in the Plan on the first day of the following calendar quarter.

Contributions

Each year, participants may contribute from 1% to 70% of their eligible pre-tax compensation, up to the maximum allowed under the Code. Participants who are age 50 or older during the Plan year are eligible to contribute additional pre-tax catch-up contributions. Beginning in 2023, a Roth 401(k) feature was added to the Plan; where participants may elect to make after-tax Roth 401(k) contributions. The Plan accepts rollover contributions from other employers' qualified plans and from conduit Individual Retirement Accounts.

Each participating company may make discretionary matching contributions, or Employer Contributions, to the Plan each year on behalf of its eligible employees. Prior to 2023, certain participating companies made discretionary profit sharing contributions as Employer Contributions on behalf of its eligible employees. In 2023, these companies replaced the profit sharing feature with the discretionary matching contribution feature. Participants are generally eligible to receive Employer Contributions, if any, if they are active employees on the last day of the Plan year and are credited with at least 1,000 hours of service during the Plan year. Employer Contributions, if any, are deposited and allocated to the accounts of eligible participants after each Plan year-end.

Participant Accounts

Participants direct the investment of their accounts into various investment options offered by the Plan. Each participant's account is credited with the participant's contributions, allocations of discretionary Employer Contributions, and investment income or losses, which consists of interest, dividends, and the net realized and unrealized investment gains and losses, less administrative expenses, for the investment option in which that account is invested. The benefit to which a participant is entitled is the participant's vested account balance.

The investment option that allows participants to invest in Omnicom Group Inc. common stock, or Company Stock, has been designated as an Employee Stock Ownership Plan, or ESOP. Participants may elect to receive any dividends paid on their vested shares held in the ESOP as a cash payment instead of being reinvested in the Plan.

Vesting

Participants vest in prior employer profit sharing contributions according to the following schedule:

0	%	for less than 2 years,
20	%	for 2 years but less than 3 years,
50	%	for 3 years but less than 4 years,
70	%	for 4 years but less than 5 years,
100	%	for 5 years or more.

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Participants vest in any employer matching contributions according to one of the following schedules, as adopted by each participating company:

(i)	0	%	for less than 2 years,
40	%	for 2 years but less than 3 years,
100	%	for 3 years or more; or,
(ii)	0	%	for less than 2 years,
20	%	for 2 years but less than 3 years,
50	%	for 3 years but less than 4 years,
70	%	for 4 years but less than 5 years,
100	%	for 5 years or more.

In addition, the Plan maintains certain more favorable vesting schedules, which were grandfathered for eligible participants when retirement plans separately sponsored by subsidiaries of the Company were merged into the Plan.

Forfeitures

Forfeited non-vested account balances may be used to reduce Employer Contributions or pay Plan expenses. Forfeitures of $6.2 million and $6.6 million were used to reduce Employer Contributions at December 31, 2023 and 2022, respectively. The Employer Contribution receivable at December 31, 2023 and 2022 reflects the reduction of the forfeitures for those years.

Benefit Payments

Upon termination of employment, retirement, disability or death, participants, or their beneficiaries, may elect to receive the vested portion of their account in the form of a direct rollover, a lump-sum distribution, partial lump-sum distributions, or annual installment payments for up to 20 years. Terminated participants may defer payment of their account until they are required to receive a distribution in accordance with the Code. The Plan provides that accounts of terminated participants are distributed if their vested balance is $1,000 or less. The Plan also allows hardships withdrawals, if certain conditions are met, and has an in-service withdrawal provision for employees who are age 59 ½ or older.

Notes Receivable from Participants

Generally, participants who are active employees may borrow from their accounts a minimum amount of $1,000 up to a maximum amount equal to the lesser of $50,000 or 50% of their vested account balance. Loans are secured by the balance in the participant's account and bear interest at 1% above the prime rate in effect at the time the loan was initiated. Interest rates for outstanding loans range from 3.25% to 9.50% and 3.25% to 8.00% at December 31, 2023 and 2022, respectively. Principal and interest are generally repaid through payroll deductions. General purpose loans must be repaid within five years and loans granted for principal residences must be repaid within 15 years. However, loans granted for principal residences that were transferred from merged plans may have longer maturity dates.

Changes to Investment Options

The Committee periodically reviews the Plan's investment options and may change the investment options available to the participants. Effective December 15, 2023, three investment options, the JPMorgan Large Cap Growth Fund Class R6, Fidelity Diversified International Commingled Pool Class A, and Fidelity Contrafund Commingled Pool Class A were replaced with similar investment options, the JPMCB Large Cap Growth Fund CF-A Class, Fidelity Diversified International Commingled Pool Class C and Fidelity Contrafund Commingled Pool Class D. Effective December 29, 2022, four investment options, the T. Rowe Price Large Cap Core Growth Fund, State Street Global All Cap Equity ex-U.S. Index Fund Class K, State Street Russell Small/Mid Cap Index Fund Class C, and State Street U.S. Bond Index Fund Class C, were replaced with similar investment options, the JPMorgan Large Cap Growth Fund Class R6, State Street Global All Cap Equity ex-U.S. Index Fund Class II, State Street Russell Small/Mid Cap Index Fund Class II, and State Street U.S. Bond Index Fund Class XIV.

Administrative Expenses

Expenses arising from participants' individual investment elections or transactions, including loan set up fees, are paid directly by the participants. Participants with balances of $1,000 or more are charged a recordkeeping fee of $34 per year and an administrative fee of $12 per year. The direct participant expenses, recordkeeping fees and administrative fees are included in administrative expenses in the Statements of Changes in Net Assets Available for Benefits.

Assets Transferred into Plan

In 2023, two separate retirement plans sponsored by subsidiaries of the Company (the TechAspect 401(k) Plan and the Propeller Consulting LLC 401(k) Plan) were merged into the Plan and assets aggregating approximately $5.0 million were transferred into the Plan. In 2022, two separate retirement plans sponsored by subsidiaries of the Company (the Archbow

5

Consulting, LLC 401(k) Profit Sharing Plan and Trust, and the Jump Media 450 401(k) Plan) were merged into the Plan and assets aggregating approximately $2.3 million were transferred into the Plan. Additional subsidiaries may merge their plan assets into the Plan in the future.

2. Summary of Significant Accounting Policies

Basis of Accounting

The Plan's financial statements are prepared on the accrual basis of accounting in conformity with generally accepted accounting principles in the United States, or U.S. GAAP.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires the Plan's management to make estimates and assumptions that affect the reported amounts of assets and liabilities, additions to and deductions from net assets, and disclosure of contingent assets and liabilities. Actual results could differ from those estimates and assumptions and the difference could be material.

Investments

Investments in funds of registered investment companies (mutual funds) are stated at fair value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Shares of mutual funds are valued at quoted market prices.

Shares of certain common/collective trusts are valued at the net asset value, or NAV, as reported by the trustees and are based on the fair value of the underlying net assets. The NAV is used as a practical expedient to estimate fair value. Each common/collective trust provides for daily redemption at the reported NAV per share with no advance notice. There were no unfunded commitments as of December 31, 2023 and 2022. Shares of Company Stock are valued at the closing price as reported on The New York Stock Exchange.

The Fidelity Managed Income Portfolio II, or MIP II, is a common/collective trust that holds fully benefit-responsive investment contracts (see Note 3) and is stated at contract value. Contract value is the relevant measurement attribute for fully benefit-responsive investment contracts because contract value is the amount participants would receive if they were to initiate permitted transactions under the Plan.

Purchases and sales of investments are recorded on the trade date. Dividends are recorded on the ex-dividend date. Interest income is recorded on the accrual basis. The net appreciation (depreciation) in the fair value of investments consists of the net realized and unrealized investment gains and losses.

Fair Value Measurement

The Plan applies the fair value measurement guidance for its financial assets and liabilities that are required to be measured at fair value on a recurring basis. The measurement of fair value requires the use of techniques based on observable and unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect the Plan's market assumptions. The inputs establish the following fair value hierarchy:

Level 1 - Unadjusted quoted prices in active markets for identical assets or liabilities.

Level 2 - Unadjusted quoted prices in active markets for similar assets or liabilities; unadjusted quoted prices for identical assets or liabilities in markets that are not active; and model-derived valuations with observable inputs.

Level 3 - Unobservable inputs for the asset or liability.

Investments where fair value is measured using NAV as a practical expedient are not categorized in the fair value hierarchy.

Notes Receivable from Participants

Notes receivable from participants are measured at the unpaid principal balance, plus any accrued interest. As provided for in the Plan, delinquent notes receivable are classified as benefit payments and are reflected in the statements of changes in net assets available for benefits.

Benefit Payments

Benefits are recorded when paid.

Risk and Uncertainties

The Plan provides participants with various investment options. Investment securities, in general, are exposed to various risks, such as interest rate risk, credit risk, liquidity risk, foreign currency risk, economic changes, and overall market volatility risk. The value of the Plan's investments is subject to volatility. Due to the level of risk associated with certain investment securities, it is reasonably possible that changes in the values of investment securities will occur in the near term and that such changes could materially affect the amounts reported in the financial statements and participants' account balances.

6

In addition. global economic challenges, including geopolitical events, international hostilities, acts of terrorism, public health crises, high and sustained inflation, high interest rates, and labor and supply chain issues could cause economic uncertainty and volatility. The future impact on the Plan's net assets available for benefits and changes in net assets available for benefits is uncertain.

3. Investment in Fully Benefit Responsive Contracts

The underlying assets of MIP II are comprised of fixed income securities, including U.S. Treasury and agency bonds, publicly traded investment grade corporate debt, asset-backed securities, and other debt securities, and money market funds. The securities are "wrapped" by synthetic investment contracts that provide liquidity for participant withdrawals by maintaining a constant net asset value. The issuers of the wrap contracts guarantee a minimum rate of return and provide full benefit responsiveness. Wrap contracts are purchased from issuers rated in the top three long-term rating categories (A- or the equivalent and above). The contract value of MIP II is determined by the Trustee and is equal to the sum of all of the benefits owed to participants. Participants may ordinarily direct the withdrawal or transfer of all or a portion of their investment in MIP II at contract value. At December 31, 2023 and 2022, there were no reserves against the wrap contracts carrying value due to the credit risk of the issuers. The interest crediting rates for MIP II at December 31, 2023 and 2022 were 2.13% and 1.75%, respectively.

4. Investments

Investments measured at fair value:

December 31,
2023	2022
Omnicom Group Inc. Common Stock	$	108,884,573	$	109,063,044
Fidelity 500 Index Fund	543,018,300	443,519,268
Fidelity Contrafund Commingled Pool Class D	408,781,341	-
Fidelity Contrafund Comingled Pool Class A	-	316,704,121
JPMCB Large Cap Growth CF-A Class	196,375,618	-
T. Rowe Price Institutional Large Cap Value Fund	157,533,317	158,808,157
JPMorgan Large Cap Growth Fund Class R6	-	150,473,323
Fidelity Diversified International Commingled Pool Class C	153,712,747	-
Fidelity Diversified International Commingled Pool Class A	-	139,551,111
AB Discovery Value Fund Class Z	131,342,805	120,640,843
William Blair Small-Mid Cap Growth CIT	120,930,627	108,513,700
PIMCO Total Return Fund Institutional Class	103,914,008	104,049,906
Vanguard FTSE Social Index Fund IS	59,096,848	43,586,420
State Street Russell Small/Mid Cap Index Fund Class II	28,050,357	23,330,658
State Street U.S. Bond Index Fund Class XIV	22,964,709	22,757,608
State Street Global All Cap Equity Ex-U.S. Index Fund Class II	17,714,848	14,194,591
FIAM Blend Target Date Income Commingled Pool Class T	7,118,708	7,151,475
FIAM Blend Target Date 2005 Commingled Pool Class T	2,922,471	2,847,997
FIAM Blend Target Date 2010 Commingled Pool Class T	9,235,328	8,701,511
FIAM Blend Target Date 2015 Commingled Pool Class T	10,718,621	10,721,363
FIAM Blend Target Date 2020 Commingled Pool Class T	35,948,358	35,750,797
FIAM Blend Target Date 2025 Commingled Pool Class T	89,360,765	80,600,944
FIAM Blend Target Date 2030 Commingled Pool Class T	140,938,437	124,595,649
FIAM Blend Target Date 2035 Commingled Pool Class T	211,502,357	177,146,331
FIAM Blend Target Date 2040 Commingled Pool Class T	253,448,441	206,827,237
FIAM Blend Target Date 2045 Commingled Pool Class T	253,843,001	203,751,715
FIAM Blend Target Date 2050 Commingled Pool Class T	280,759,507	221,465,015
FIAM Blend Target Date 2055 Commingled Pool Class T	205,518,823	150,069,464
FIAM Blend Target Date 2060 Commingled Pool Class T	108,099,829	72,258,967
FIAM Blend Target Date 2065 Commingled Pool Class T	18,615,835	8,029,435
Fidelity Government Money Market Fund	510,086	89,770
$	3,680,860,665	$	3,065,200,420

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The net appreciation (depreciation) in the fair value of investments, consisting of the net realized and unrealized investment gains and losses:

Year Ended December 31,
2023	2022
Omnicom Group Inc. Common Stock	$	6,720,279	$	11,850,690
Fidelity 500 Index Fund	105,919,001	(105,720,871)
Fidelity Contrafund Commingled Pool Class D	5,843,820	-
Fidelity Contrafund Comingled Pool Class A	108,671,630	(123,975,519)
JPMCB Large Cap Growth CF-A Class	2,379,168	-
T. Rowe Price Institutional Large Cap Value Fund	1,826,900	(33,665,291)
JPMorgan Large Cap Growth Fund Class R6	48,892,512	(288,776)
T. Rowe Price Institutional Large Cap Core Growth Fund	-	(103,644,930)
Fidelity Diversified International Commingled Pool Class C	3,252,243	-
Fidelity Diversified International Commingled Pool Class A	20,618,019	(44,252,951)
AB Discovery Value Fund Class Z	11,370,526	(33,143,118)
William Blair Small-Mid Cap Growth CIT	18,836,549	(33,589,227)
PIMCO Total Return Fund Institutional Class	2,307,484	(22,863,974)
Vanguard FTSE Social Index Fund IS	13,184,569	(13,727,377)
State Street Russell Small/Mid Cap Index Fund Class II	5,502,925	(53,845)
State Street U.S. Bond Index Fund Class XIV	1,240,721	(91,995)
State Street Global All Cap Equity Ex-U.S. Index Fund Class II	2,335,684	(100,268)
State Street Global All Cap Equity Ex-U.S. Index Fund Class K	-	(2,466,909)
State Street Russell Small/Mid Cap Index Fund Class C	-	(7,847,324)
State Street U.S. Bond Index Fund Class C	-	(3,434,226)
FIAM Blend Target Date Income Commingled Pool Class T	542,322	(1,138,308)
FIAM Blend Target Date 2005 Commingled Pool Class T	227,208	(448,283)
FIAM Blend Target Date 2010 Commingled Pool Class T	824,618	(1,391,054)
FIAM Blend Target Date 2015 Commingled Pool Class T	1,136,628	(1,992,296)
FIAM Blend Target Date 2020 Commingled Pool Class T	4,293,599	(7,817,888)
FIAM Blend Target Date 2025 Commingled Pool Class T	11,153,189	(17,319,697)
FIAM Blend Target Date 2030 Commingled Pool Class T	19,004,270	(27,221,993)
FIAM Blend Target Date 2035 Commingled Pool Class T	31,360,157	(39,116,480)
FIAM Blend Target Date 2040 Commingled Pool Class T	41,552,214	(48,020,473)
FIAM Blend Target Date 2045 Commingled Pool Class T	42,392,065	(47,366,559)
FIAM Blend Target Date 2050 Commingled Pool Class T	46,357,723	(49,655,292)
FIAM Blend Target Date 2055 Commingled Pool Class T	32,698,475	(31,375,218)
FIAM Blend Target Date 2060 Commingled Pool Class T	16,324,229	(13,661,259)
FIAM Blend Target Date 2065 Commingled Pool Class T	2,331,614	(873,195)
$	609,100,341	$	(804,413,906)

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5. Fair Value

Investments measured at fair value on a recurring basis:

December 31, 2023
Level 1	Level 2	Level 3	Total
Mutual Funds	$	995,415,364	$	-	$	-	$	995,415,364
Company Stock	108,884,573	-	-	108,884,573
Common/Collective Trusts measured at NAV as a practical expedient	-	-	-	2,576,560,728
$	1,104,299,937	$	-	$	-	$	3,680,860,665

December 31, 2022
Level 1	Level 2	Level 3	Total
Mutual Funds	$	1,021,167,687	$	-	$	-	$	1,021,167,687
Company Stock	109,063,044	-	-	109,063,044
Common/Collective Trusts measured at NAV as a practical expedient	-	-	-	1,934,969,689
$	1,130,230,731	$	-	$	-	$	3,065,200,420

6. Party-In-Interest Transactions

Certain investments are managed by the Trustee or certain of its affiliates. These investments qualify as exempt party-in-interest transactions under ERISA. Fees paid by the Plan for investment related services are included in net appreciation (depreciation) in fair value of investments in the statements of changes in net assets available for benefits.

One of the Plan's investment options invests exclusively in Company Stock. At December 31, 2023 and 2022, the Plan owned 1,258,561 and 1,337,000 shares of Company Stock, respectively, with corresponding fair values of $108.9 million and $109.1 million, respectively.

Additionally, participants who are active employees may borrow from their accounts and such loans qualify as exempt party-in-interest transactions under ERISA. These loans are recorded as notes receivable from participants in the statements of net assets available for benefits.

7. Plan Amendment or Termination

The Company or its delegate has the right to amend the Plan at any time. In addition, although it has not expressed any intent to do so, the Company has the right under the Plan to discontinue its contributions at any time and to terminate the Plan, subject to the provisions of ERISA. In the event of Plan termination or the complete discontinuance of contributions by the Company under the Plan, the participants' accounts will become fully vested in accordance with the terms of the Plan.

8. Tax Status

The Plan is a retirement plan that is designed to satisfy the qualification requirements under Section 401(a) of the Code and therefore, is not subject to tax under present income tax regulations. The Internal Revenue Service, or IRS, has determined and informed the Company by letter dated November 20, 2015, that the terms of the Plan and related trust comply with applicable sections of the Code. Although the Plan has been amended since receiving the determination letter, the Plan administrator and the Plan's counsel believe that the Plan is designed and is currently being operated in compliance with the applicable requirements of the Code.

U.S. GAAP requires the Plan's management to evaluate tax positions taken by the Plan and recognize a tax liability or asset if the Plan has taken an uncertain position that more likely than not would not be sustained upon examination by the IRS. The Plan's management has analyzed the tax positions taken by the Plan, and has concluded that as of December 31, 2023, there were no uncertain positions taken or expected to be taken that would require recognition of a liability or asset or disclosure in the Plan's financial statements. The Plan is subject to routine examination by various taxing jurisdictions. Currently, there are no open examinations for any period.

9. Subsequent Events

The Committee evaluated events subsequent to the date of the statement of net assets available for benefits and determined there have not been any other events that have occurred that would require adjustment to or disclosure in the financial statements.

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OMNICOM GROUP RETIREMENT SAVINGS PLAN

Schedule H, Line 4i - Schedule of Assets (Held at End of Year)

December 31, 2023

EIN: 13-1514814

Plan No. 004

(a)	(b)	(c)	(d)	(e)
Identity of issue, borrower, lessor or similar party	Description of investment, including maturity date, rate of interest, collateral, par or maturity value	Shares	Cost	Current value
*	Omnicom Group Inc. Common Stock	Common Stock $0.15 par value	1,258,561	a	$	108,884,573
*	Fidelity Managed Income Portfolio II	Common/Collective Trust	223,515,655	a	223,600,010
*	Fidelity 500 Index Fund	Mutual Fund	3,281,276	a	543,018,300
*	Fidelity Contrafund Commingled Pool Class D	Common/Collective Trust	12,151,645	a	408,781,341
JPMCB Large Cap Growth CF-A Class	Common/Collective Trust	2,373,119	a	196,375,618
T. Rowe Price Institutional Large Cap Value Fund	Mutual Fund	7,020,201	a	157,533,317
*	Fidelity Diversified International Commingled Pool Class C	Common/Collective Trust	8,768,611	a	153,712,747
AB Discovery Value Fund Class Z	Mutual Fund	6,201,266	a	131,342,805
William Blair Small-Mid Cap Growth CIT	Common/Collective Trust	3,202,061	a	120,930,627
PIMCO Total Return Fund Institutional Class	Mutual Fund	12,013,180	a	103,914,008
Vanguard FTSE Social Index Fund IS	Mutual Fund	1,814,456	a	59,096,848
State Street Russell Small/Mid Cap Index Fund Class II	Common/Collective Trust	1,784,828	a	28,050,357
State Street U.S. Bond Index Fund Class XIV	Common/Collective Trust	2,163,013	a	22,964,709
State Street Global All Cap Equity Ex-U.S. Index Fund Class II	Common/Collective Trust	1,331,343	a	17,714,848
*	FIAM Blend Target Date Income Commingled Pool Class T	Common/Collective Trust	439,760	a	7,118,708
*	FIAM Blend Target Date 2005 Commingled Pool Class T	Common/Collective Trust	164,739	a	2,922,471
*	FIAM Blend Target Date 2010 Commingled Pool Class T	Common/Collective Trust	462,692	a	9,235,328
*	FIAM Blend Target Date 2015 Commingled Pool Class T	Common/Collective Trust	509,682	a	10,718,621
*	FIAM Blend Target Date 2020 Commingled Pool Class T	Common/Collective Trust	1,680,522	a	35,948,358
*	FIAM Blend Target Date 2025 Commingled Pool Class T	Common/Collective Trust	3,888,632	a	89,360,765
*	FIAM Blend Target Date 2030 Commingled Pool Class T	Common/Collective Trust	5,924,272	a	140,938,437
*	FIAM Blend Target Date 2035 Commingled Pool Class T	Common/Collective Trust	8,060,303	a	211,502,357
*	FIAM Blend Target Date 2040 Commingled Pool Class T	Common/Collective Trust	9,380,031	a	253,448,441
*	FIAM Blend Target Date 2045 Commingled Pool Class T	Common/Collective Trust	9,311,922	a	253,843,001
*	FIAM Blend Target Date 2050 Commingled Pool Class T	Common/Collective Trust	10,448,809	a	280,759,507
*	FIAM Blend Target Date 2055 Commingled Pool Class T	Common/Collective Trust	7,133,593	a	205,518,823
*	FIAM Blend Target Date 2060 Commingled Pool Class T	Common/Collective Trust	5,598,127	a	108,099,829
*	FIAM Blend Target Date 2065 Commingled Pool Class T	Common/Collective Trust	1,230,392	a	18,615,835
*	Fidelity Government Money Market Fund	Mutual Fund	510,086	a	510,086
*	Notes receivable from participants	Participant Loans**	-	21,522,758
$	3,925,983,433
* Represents a party-in-interest as defined by ERISA.
** Maturity dates through May 2042. Interest rates range from 3.25% to 9.50%.
a - The cost of participant-directed investments is not required to be disclosed.

See report of independent registered public accounting firm.

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Administrative Committee of the Plan has duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.

	OMNICOM GROUP RETIREMENT SAVINGS PLAN
Dated:	June 27, 2024	/s/ Leslie Chiocco
	Leslie Chiocco Member of Administrative Committee

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