Material Agreement Form 8 K

Item 1.01 Entry into a Material Definitive Agreement.

On December 8, 2024, Omnicom Group Inc., a New York corporation ( "Omnicom"), entered into an Agreement and Plan of Merger (the "Merger Agreement"), by and among Omnicom, EXT Subsidiary Inc., a Delaware corporation and a direct wholly owned subsidiary of Omnicom ("Merger Sub"), and The Interpublic Group of Companies, Inc., a Delaware corporation ("IPG"), pursuant to which, subject to the terms and conditions of the Merger Agreement, Merger Sub will merge with and into IPG (the "Merger"), with IPG surviving the Merger as a direct wholly owned subsidiary of Omnicom. All defined terms used in this summary of the Merger Agreement that are not otherwise defined herein have the meanings ascribed to such terms in the Merger Agreement.

The Merger

Subject to the terms and conditions of the Merger Agreement, at the date and time the Merger becomes effective (the "Effective Time"), each share of common stock, par value $0.10 per share, of IPG ("IPG common stock") issued and outstanding immediately prior to the Effective Time (other than certain excluded shares) will be converted into and thereafter represent the right to receive 0.344 shares of common stock (the "Exchange Ratio"), $0.15 par value per share, of Omnicom (the "Omnicom common stock") and, if applicable, cash in lieu of fractional shares (the "Merger Consideration").

Treatment of Stock Options and Stock-Based Awards

As of the Effective Time, each option to acquire shares of IPG common stock granted by IPG (each, an "IPG Stock Option") that is outstanding and unexercised immediately prior to the Effective Time, whether or not then vested or exercisable, will be assumed by Omnicom and will be automatically converted into an option to acquire shares of Omnicom common stock. Each such IPG Stock Option as so assumed and converted (after such conversion, an "Assumed Option") will continue to have, and will be subject to, the same terms and conditions as applied to the IPG Stock Option immediately prior to the Effective Time, except that, as of the Effective Time, each such Assumed Option will constitute an option to acquire that number of whole shares of Omnicom common stock (rounded down to the nearest whole share) equal to the product of (A) the number of shares of IPG common stock subject to such IPG Stock Option immediately prior to the Effective Time multiplied by (B) the Exchange Ratio, at an exercise price per share of Omnicom common stock (rounded up to the nearest whole cent) equal to the quotient obtained by dividing (x) the exercise price per share of such IPG Stock Option by (y) the Exchange Ratio. It is expected that the Merger will qualify as a tax-freereorganization for U.S. federal income tax purposes.

As of the Effective Time, each time-based restricted stock unit with respect to shares of IPG common stock granted by IPG (each, an "IPG RSU") that is outstanding immediately prior to the Effective Time will be assumed by Omnicom and will be automatically converted into a cash award equal to the fair market value of the corresponding number of shares of IPG common stock underlying such IPG RSU, based on the closing price of such shares on the last day on which shares of IPG common stock are traded on the New York Stock Exchange (the "NYSE") prior to the Closing. Each such IPG RSU as so assumed and converted will continue to have, and will be subject to, the same terms and conditions as applied to such IPG RSU immediately prior to the Effective Time, except that such IPG RSU so assumed and converted will be settled in cash in lieu of shares of IPG common stock.

As of the Effective Time, each performance share award granted by IPG (each, an "IPG PSU") that is outstanding immediately prior to the Effective Time will be assumed by Omnicom and will be converted into a cash award equal to the fair market value of the corresponding number of shares of IPG common stock underlying such IPG PSU (the number of shares of IPG common stock subject to an IPG PSU will be determined based on the target level of performance, or, if the performance period in respect of such IPG PSU ended on or prior to the Effective Time, the greater of actual and target level performance), based on the closing price of such shares on the last day on which shares of IPG common stock are traded on the NYSE prior to the closing of the Merger. Each such IPG PSU as so assumed and converted will continue to have, and will be subject to, the same terms and conditions as applied to such IPG PSU immediately prior to the Effective Time (excluding any performance-based vesting conditions), except that such IPG PSU will be settled in cash in lieu of shares of IPG common stock.

As of the Effective Time, each restricted stock award with respect to shares of IPG common stock granted by IPG (each, an "IPG RSA") that is outstanding immediately prior to the Effective Time will be assumed by Omnicom and will be automatically converted into a restricted stock award with respect to shares of Omnicom common stock.

Each such IPG RSA as so assumed and converted (after such conversion, an "Assumed RSA") will continue to have, and will be subject to, the same terms and conditions as applied to such IPG RSA immediately prior to the Effective Time, except that, as of the Effective Time, each such Assumed RSA will be a restricted stock award covering that number of whole shares of Omnicom common stock (rounded down to the nearest whole share) equal to the product of (A) the number of shares of IPG common stock subject to such IPG RSA immediately prior to the Effective Time multiplied by (B) the Exchange Ratio.

Each award granted under the IPG Restricted Cash Plan (each, an "IPG Restricted Cash Award") and each performance cash award granted under an IPG Stock Plan (each, an "IPG Performance Cash Award" and, together with the IPG Restricted Cash Awards, the "IPG Cash Awards") that, in each case, is outstanding immediately prior to the Effective Time will be assumed by Omnicom, and each such IPG Cash Award as so assumed will continue to have, and will be subject to, the same terms and conditions as applied to such IPG Cash Award immediately prior to the Effective Time, provided that the payment opportunity in respect of any IPG Performance Cash Award will equal the target amount of such IPG Performance Cash Award as in effect immediately prior to the Effective Time or, if the performance period in respect of such IPG Performance Cash Award ended on or prior to the Effective Time, the greater of the target amount and the amount determined based on actual performance.

Additionally, all IPG Stock Options, IPG RSUs and IPG RSAs held by non-employeemembers of the IPG Board will be fully vested immediately prior to the Effective Time.

Post-Closing Governance

In connection with the consummation of the Merger, Omnicom will increase the size of Omnicom's board of directors (the "Omnicom Board") to add three directors designated by IPG, one of whom will be Philippe Krakowsky, currently the Chief Executive Officer of IPG (collectively, the "IPG Director Nominees"). Subject to the fiduciary duties of the Omnicom Board, applicable laws and the rules and regulations of NYSE, Omnicom will nominate the IPG Director Nominees for election to the Omnicom Board at the first annual meeting of the stockholders of Omnicom after the Closing Date.

In addition, in connection with the consummation of the Merger, Omnicom will take all actions necessary to cause Philippe Krakowsky to be appointed as Co-Presidentand Co-ChiefOperating Officer of Omnicom and co-chairof the Management Integration Committee of Omnicom.

Conditions to the Merger

Completion of the Merger is subject to the satisfaction or waiver of certain conditions including (a) the adoption of the Merger Agreement by the IPG stockholders; (b) the approval of the issuance of shares of Omnicom common stock in connection with the Merger by Omnicom's stockholders; (c) the effectiveness of Omnicom's registration statement on Form S-4;(d) the approval for listing the shares of Omnicom common stock issuable to the stockholders of IPG pursuant to the Merger Agreement on the NYSE; (e) the receipt of approvals under certain applicable antitrust and foreign investment laws; (f) the absence of any law or order prohibiting the consummation of the Merger; (g) a customary "bringdown" of Omnicom's and IPG's representations and warranties; (h) compliance by Omnicom and IPG with the covenants in the Merger Agreement in all material respects and (i) the absence of a material adverse effect on either Omnicom or IPG.

Representations, Warranties and Covenants

The Merger Agreement contains mutual customary representations and warranties of Omnicom and IPG relating to their respective businesses and public filings. The Merger Agreement also contains customary mutual pre-closingcovenants, including the obligation of Omnicom and IPG to conduct their businesses in the ordinary course of business consistent with past practice and to refrain from taking certain specified actions without the consent of the other party.

Omnicom and IPG have each agreed to customary non-solicitationobligations related to soliciting or engaging in any discussions or negotiations regarding competing proposals. Notwithstanding such non-solicitationobligations, prior to obtaining stockholder approval and under certain specified circumstances, the Omnicom Board or the IPG Board, in each case, may change its recommendation of the transaction but may not terminate the Merger Agreement in connection with such change in recommendation.

Termination

The Merger Agreement contains provisions granting each of Omnicom and IPG the right to terminate the Merger Agreement under specified circumstances, including: (a) if a permanent legal prohibition enjoins the consummation of the Merger; (b) if the Merger is not completed by December 8, 2025 (which date may be extended to June 8, 2026 if certain regulatory approvals have not been obtained); (c) if either party fails to obtain stockholder approval; (d) if the other party has breached its representations or warranties or failed to perform its covenants in the Merger Agreement in a way that would entitle the party seeking to terminate the Merger Agreement not to consummate the Merger, subject to cure rights of the breaching party; or (e) if the other party's board of directors has changed or withdrawn its recommendation in connection with the Merger or committed a willful and material breach of its non-solicitationobligations.

If the Merger Agreement is terminated due to Omnicom's board of directors changing or withdrawing its recommendation in connection with the Merger, or due to Omnicom committing a willful and material breach of its non-solicitationobligations, Omnicom will be required to pay to IPG $676,000,000. If the Merger Agreement is terminated due to IPG's board of directors changing its recommendation in connection with the Merger, or due to IPG committing a willful and material breach of its non-solicitationobligations, then IPG will be required to pay Omnicom $439,000,000. In addition, if the Merger Agreement is terminated due to either party's failure to obtain stockholder approval, Omnicom or IPG, as applicable, will be required to reimburse the other party for its expenses incurred in connection with the transaction in an amount not to exceed $25 million.

The Merger Agreement is attached hereto as Exhibit 2.1 and is incorporated herein by reference. The foregoing description does not purport to be complete and is subject to and qualified in its entirety by reference to the Merger Agreement.

The Merger Agreement has been included to provide security holders and investors with information regarding its terms. It is not intended to provide any other factual information about Omnicom, IPG or any other person. The representations, warranties and covenants contained in the Merger Agreement were made solely for purposes of the Merger Agreement and as of specific dates, were solely for the benefit of the parties to the Merger Agreement, may be subject to limitations agreed upon by the contracting parties, including being qualified by confidential disclosures made for the purposes of allocating contractual risk between the parties to the Merger Agreement instead of establishing these matters as facts, and may be subject to standards of materiality applicable to the contracting parties that differ from those applicable to security holders. Security holders and investors are not third-party beneficiaries under the Merger Agreement and should not rely on the representations, warranties and covenants or any descriptions thereof as characterizations of the actual state of facts or condition of Omnicom or IPG. Moreover, information concerning the subject matter of the representations and warranties may change after the date of the Merger Agreement, which subsequent information may or may not be fully reflected in Omnicom's or IPG's public disclosures.