WPP WPP PLC

NOTES TO FINANCIAL STATEMENTS

DECEMBER 31, 2016 AND 2015, AND FOR THE YEAR ENDED DECEMBER 31, 2016

The following description of the Ogilvy & Mather Savings and Investment Plan (the “Plan”), as amended and restated effective January 1, 2011, is provided for general information purposes only. Participants should refer to the Plan document for a more complete description of the Plan’s provisions. Effective July 1, 2014, the Plan name was changed from the Ogilvy & Mather Profit Sharing Retirement and 401(k) Plan to the Ogilvy & Mather Savings and Investment Plan.

General

The Plan is a defined contribution plan sponsored by The Ogilvy Group, LLC (the “Company”), a wholly-owned subsidiary of WPP plc. The Plan covers all full-time, part-time and eligible temporary employees of The Ogilvy Group, LLC, A. Eicoff & Company, Inc., Ogilvy Public Relations Worldwide Inc., Soho Square Public Relations, Inc., Feinstein Kean Healthcare, Soho Square, LLC, Geometry Global, LLC, Effective UI, Inc., and Maxx Marketing, Inc. (collectively the “Companies”).

Mercer HR Services, LLC, is the Record Keeper and Trustee of the Plan. The Plan is subject to the provisions of the Employee Retirement Income Security Act of 1974 (“ERISA”).

The Plan is administered by the Retirement Plan Committee (“Committee”), which was established by the Board of Directors of the Company.

Contributions/Eligibility

Deferred Contributions

Participants may elect to make 401(k) contributions in an amount from 1% to 50% of their eligible compensation in any calendar year. These contributions constitute salary reductions and are subject to tax deferral under the Internal Revenue Code (“IRC”). In addition, participants may make Roth elective deferrals to their account. Participants direct the investment of their contributions into various investment options offered by the Plan.

Eligible employees hired on or after April 1, 2013 are automatically enrolled in the Plan at a deferral rate of 4% of their eligible compensation, unless the employee elects prior to his or her date of Plan participation either not to defer compensation or to defer a larger or smaller percentage of compensation. Such election must be made in writing, or via telephone or internet access to the Company’s Benefits Department. An employee who is automatically enrolled in the Plan on or after July 1, 2014, and who has not opted out of contributing by their one year anniversary of their auto-enrollment date, will have his or her salary reduction contribution percentage escalated once by 1%.

For Plan years 2016 and 2015, eligible compensation is limited to $265,000. The maximum 401(k) contribution as established by the Internal Revenue Service (“IRS”) for the years ended December 31, 2016 and 2015, was $18,000.

Catch-up Contributions

In addition, participants who have attained the age of 50 before the close of the Plan year, may make catch-up contributions in accordance with the IRC. The maximum amount of catch-up contributions for the years ended December 31, 2016 and 2015, was $6,000.

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OGILVY & MATHER SAVINGS AND INVESTMENT PLAN

NOTES TO FINANCIAL STATEMENTS

DECEMBER 31, 2016 AND 2015, AND FOR THE YEAR ENDED DECEMBER 31, 2016

All employees are eligible to participate in the Plan, except employees who are: (a) covered by collective bargaining agreements, unless otherwise stipulated in such collective bargaining agreements, (b) non-resident aliens, (c) leased employees or independent contractors and, (d) experiential field employees. Effective July 1, 2014, employees who are determined to be temporary, part-time or contingent employees are eligible to participate on the first day of the month coinciding with, or next following, the completion of one year of service, as defined in the Plan. All other employees are eligible to participate on the first day of the month coinciding with, or next following, the ninety day anniversary of the employment commencement date, as defined.

Employer Contributions

Effective July 1, 2014, eligible employees of the Companies (other than Effective UI, Inc.) who are hired on or after July 1, 2014, or employees who are rehired or transferred to a company on or after July 1, 2014 and who are not eligible to accrue a benefit under the Ogilvy & Mather Account Balance Defined Benefit Pension Plan, are entitled to an employer matching contribution and an annual true-up matching contribution. The matching contribution shall be equal to the first 5% of the participant’s compensation that is deferred into the Plan for each payroll period. The annual true-up employer matching contribution will be credited to those participants who did not receive an employer matching contribution in the amount of 100% of the first 5% of compensation contributed during the Plan year. Catch-up contributions are not eligible for matching contributions. Employer contributions to the Plan for those eligible employees hired prior to July 1, 2014 are made at the discretion of the management of the Companies. Effective January 1, 2016, eligible employees of Effective UI, Inc. are entitled to an employer matching contribution equal to the first 2% of their compensation deferred into the Plan for each payroll period.

Participant Accounts

Each participant’s account is credited with the participant’s contribution, the allocation of employer contributions and Plan earnings, and charged with withdrawals and an allocation of Plan losses and administrative expenses. The benefit to which a participant is entitled is the benefit that can be provided from the participant’s vested account balance.

Investments

Participants direct the investment of their account balances from among various investment options offered by the Plan. The Plan offers a number of mutual funds, a common collective trust fund and the WPP Stock Fund, which invests in American Depositary Shares of WPP plc (“WPP plc ADSs”).

Forfeited Accounts

At December 31, 2016 and 2015, forfeited non-vested accounts totaled $865,452 and $172,028, respectively. These amounts can be used to reduce future employer contributions or pay administrative expenses under the Plan. During 2016, no forfeiture amounts were used for these purposes.

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OGILVY & MATHER SAVINGS AND INVESTMENT PLAN

NOTES TO FINANCIAL STATEMENTS

DECEMBER 31, 2016 AND 2015, AND FOR THE YEAR ENDED DECEMBER 31, 2016

Vesting

Prior to July 1, 2014, all participants, other than those transferred from the OPR 401(k) Plan (“OPR Participants”), are fully vested in their accounts at all times. Elective employee 401(k) contributions and earnings thereon are always fully vested. Participants are also fully vested in their Roth elective deferrals.

OPR Participants, whose accounts include prior employer contributions that were transferred into the Plan, vest in those contributions as follows:

Participants hired after July 1, 2014 are vested in their employer matching contributions subject to a 3-year cliff vesting schedule.

Notes Receivable from Participants

Eligible employees can request a Plan loan. Only two personal loans and one residential loan can be outstanding at any time. Participants may borrow from their fund accounts a minimum of $1,000 up to a maximum equal to the lesser of $50,000 or 50% of their vested account balance. The notes are secured by the balance in the participant’s account and bear interest at rates commensurate with local prevailing rates as determined quarterly by the Committee. Loan repayment terms are generally five and fifteen years for personal and residential loans, respectively. Principal and interest are paid ratably through payroll deductions.

Upon termination of employment, a participant can: (a) pay off the entire outstanding loan balance, (b) transfer the loan to a successor employer qualified retirement plan as part of an eligible rollover distribution, or (c) elect to continue repayment in a form or manner determined by the Committee, subject to the provisions of the Plan. An eligible employee, who takes an approved unpaid leave of absence, as defined in the Plan, may discontinue payments on the loan for a period of absence up to 12 months. Upon a return to employment, the eligible employee must repay the missed payments within the original loan term. At December 31, 2016, interest rates ranged from 3.25% to 9.50% for outstanding loans.

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OGILVY & MATHER SAVINGS AND INVESTMENT PLAN

NOTES TO FINANCIAL STATEMENTS

DECEMBER 31, 2016 AND 2015, AND FOR THE YEAR ENDED DECEMBER 31, 2016

Payment of Benefits

Plan participants or beneficiaries, including domestic partners, are eligible to receive a benefit payment equal to their vested account balance upon termination of employment, retirement, or death, as stipulated in the Plan document. Benefits are paid in a single lump-sum payment, subject to certain restrictions as defined in the Plan. All distributions under the Plan are made in cash, except to the extent that the participant has an investment in the WPP Stock Fund and elects to have such portion of the participant’s account distributed in WPP plc ADSs held in the WPP Stock Fund. The Plan was amended in 2004 to allow for in-service age 59  ¹ ⁄ ₂ withdrawals and in-service rollover withdrawals.

The Committee may permit an eligible employee, as defined in the Plan, to withdraw all or a portion of a participant’s account balance upon the next valuation date upon hardship subject to certain provisions in the Plan. Hardships are defined in the Plan document as certain medical expenses, purchase of a primary residence, payment of certain tuition and education fees, and to prevent eviction from a participant’s primary residence. Hardships also include certain payments for burial and funeral expenses and damages to a principal residence, as defined by the IRC. A participant receiving a hardship withdrawal may not make employee contributions to any plans maintained by the Company or Companies for a period of six months.

Basis of Accounting

The financial statements of the Plan are prepared on the accrual basis of accounting in accordance with accounting principles generally accepted in the United States of America (“GAAP”).

Investment Valuation and Income Recognition

The Plan’s investments are reported 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.

Purchases and sales of securities are recorded on a trade-date basis. Interest income is recorded on the accrual basis. Dividends are recorded on the ex-dividend date. Net appreciation/depreciation includes the Plan’s gains and losses on investments bought and sold as well as held during the year.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires Plan management to make estimates and assumptions that affect the reported amounts of assets and liabilities and changes therein, and disclosure of contingent assets and liabilities. Actual results could differ from those estimates.

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OGILVY & MATHER SAVINGS AND INVESTMENT PLAN

NOTES TO FINANCIAL STATEMENTS

DECEMBER 31, 2016 AND 2015, AND FOR THE YEAR ENDED DECEMBER 31, 2016

Notes Receivable from Participants

Notes receivable from participants are measured at their unpaid principal balance plus any accrued but unpaid interest. Interest income is recorded on the accrual basis. Related fees are charged directly to the borrowing participant’s account and are included in administrative expenses when incurred. No allowance for credit losses has been recorded as of December 31, 2016 and 2015. If a participant does not make note repayments and the Plan Administrator considers the participant note to be in default, the note balance is reduced, and the delinquent participant note receivable is recorded as a benefit payment based on the terms of the Plan document.

Excess Contributions Payable

Amounts payable to participants for contributions in excess of amounts allowed by the IRS, are recorded as a liability, with a corresponding reduction to contributions. There were no excess contributions for the years ended December 31, 2016 or 2015.

Payment of Benefits

Benefits are recorded when paid.

Administrative Expenses

Certain expenses of maintaining the Plan are paid by the Plan, unless otherwise paid by the Company. Expenses that are paid by the Company are excluded from these financial statements. Fees related to the administration of notes receivable from participants are charged directly to the participant’s account and are included in administrative expenses. Investment related expenses are included in net appreciation/depreciation of fair value of investments.

Subsequent Events

The Plan’s management has evaluated subsequent events through June 27, 2017, the date the financial statements were available to be issued. On June 1, 2017, the Company authorized the August 1, 2017 merger of the Plan into The Savings & Investment Plan (“SIP”), a tax-qualified plan sponsored by an affiliate of the Company.

The framework for measuring fair value provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy under the FASB Accounting Standards Codification (ASC) 820 are described as follows: Level 1 inputs consist of unadjusted quoted prices for identical assets or liabilities in active markets that the Plan has the ability to access; Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices in markets that are not active, inputs other than quoted prices that are observable for the asset or liability, or other inputs that are derived principally from, or corroborated by, observable market data by correlation or other means. If the asset or liability has a specified (contractual) term, the Level 2 input must be observable for substantially the full term of the asset or liability. Level 3 inputs are unobservable and significant to the fair value measurement.

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OGILVY & MATHER SAVINGS AND INVESTMENT PLAN

NOTES TO FINANCIAL STATEMENTS

DECEMBER 31, 2016 AND 2015, AND FOR THE YEAR ENDED DECEMBER 31, 2016

The asset or liability’s fair value measurement level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Valuation techniques maximize the use of relevant observable inputs and minimize the use of unobservable inputs.

The following is a description of the valuation methodologies used for assets measured at fair value.

Mutual Funds

The mutual funds are valued at the daily closing price as reported by the fund. Mutual funds held by the Plan are open-end mutual funds that are registered with the Securities and Exchange Commission. These funds are required to publish their daily net asset value (“NAV”) and to transact at that price. The mutual funds held by the Plan are deemed to be actively traded.

WPP Stock Fund

The fair value of the WPP Stock Fund is based on quoted NAV of the shares held by the Plan at year-end.

The Putnam Stable Value Fund

The Putnam Stable Value Fund (“PSVF”), a common collective trust, invests directly or indirectly in fully benefit–responsive investment contracts. The PSVF is valued at the NAV as provided by the trustee, which is used as a practical expedient to estimate fair value. This practical expedient would not be used if it is determined to be probable that the fund will sell the investment for an amount different from the reported NAV. Participant transactions (purchases and sales) may occur daily. Were the Plan to initiate a full redemption of the PSVF, the issuer reserves the right to temporarily delay withdrawal from the PSVF in order to ensure that securities liquidations will be carried out in an orderly business manner. The PSVF, included in the fair value hierarchy table below, files a U.S. Department of Labor Form 5500, Annual Return/Report of Employee Benefit Plan, as a direct filing entity. Accordingly, certain disclosure requirements under FASB ASU 2015-12 with respect to investment strategies for investments measured using the net asset value practical expedient are not required in this report.

The following tables set forth by level, within the fair value hierarchy, the Plan’s investments at fair value as of December 31, 2016 and 2015.

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OGILVY & MATHER SAVINGS AND INVESTMENT PLAN

NOTES TO FINANCIAL STATEMENTS

DECEMBER 31, 2016 AND 2015, AND FOR THE YEAR ENDED DECEMBER 31, 2016

Investments Measured at Fair Value Using the Practical Expedient

The following table summarizes investments for which fair value is measured using the NAV per share practical expedient for the PSVF as of December 31, 2016, and 2015, respectively. There are no participant redemption restrictions for these investments; the redemption notice period is applicable only to the Plan.

The IRS has determined and informed the Company by a letter dated May 1, 2014, that the Plan and related Trust are designed in accordance with applicable sections of the IRC. Although the Plan has been amended since receiving the determination letter, the Plan Administrator believes that the Plan is designed, and is currently being operated, in compliance with the applicable requirements of the IRC and, therefore, believes that the Plan is qualified and the related trust is tax-exempt.

GAAP requires Plan management to evaluate tax positions taken by the Plan and recognize a tax liability if the Plan has taken an uncertain position that more likely than not would not be sustained upon examination by the IRS. The Plan is subject to routine audits by taxing jurisdictions; however, there are currently no audits for any tax periods in progress. The Plan Administrator believes it is no longer subject to income tax examinations for years prior to 2013.

The Plan provides participants the option to invest in the WPP Stock Fund, a party-in-interest. At December 31, 2016 the Plan held 80,220 WPP plc ADSs in the WPP Stock Fund, valued at $8,877,164, and at December 31, 2015 the Plan held 82,178 WPP plc ADSs in the WPP Stock Fund valued at $9,429,073.

These transactions qualify as exempt party-in-interest transactions. There have been no known prohibited transactions with parties-in-interest.

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OGILVY & MATHER SAVINGS AND INVESTMENT PLAN

NOTES TO FINANCIAL STATEMENTS

DECEMBER 31, 2016 AND 2015, AND FOR THE YEAR ENDED DECEMBER 31, 2016

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, participants would become 100% vested in their employer contributions.

The Plan invests in various investment securities. Investment securities are exposed to various risks, such as interest rate, market, and credit risks. Due to the level of risk associated with certain investment securities, it is at least reasonably possible that changes in the values of investment securities will occur in the near term and that such changes could materially affect participants’ account balances and the amounts reported in the Statements of Net Assets Available for Benefits.

During 2016, the Plan received a transfer of $38,045,008, representing all participant accounts of Geometry Global, LLC, formerly part of the SIP, a qualified plan sponsored by an affiliate of the Company.

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See accompanying Report of Independent Registered Public Accounting Firm.

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The amount listed above represents employee contributions and loan repayments that were deposited to the Plan in a delayed manner and were previously listed as delinquent contributions on the audit report for the Plan year ended December 31, 2015. The Company has fully corrected this matter by crediting all affected participant accounts with any lost earnings for the period of the delayed transfer.

See accompanying Report of Independent Registered Public Accounting Firm.

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