AMG PANTHEON INFRASTRUCTURE SUBSIDIARY FUND, LLC INVESTMENT MANAGEMENT AGREEMENT

Appointment.

Authority and Duties of the Investment Manager.

The Investment Manager agrees to develop and furnish continuously an investment program for the Fund. In this regard the Investment Manager will (i) manage the investment and reinvestment of the Fund’s assets in compliance with (A) the Fund’s investment program and policies and (B) consistent with the investment program and policies of AMG Pantheon Infrastructure Fund, LLC; (ii) provide research and analysis relative to the investment program and objectives of the Fund; (iii) determine (subject to the overall supervision and review of the Fund’s board of directors (the “Board of Directors” and each member of the Board of Directors, a “Director”) what investments will be purchased, held, sold, or exchanged by the Fund and what portion, if any, of the assets of the Fund will be held in cash or cash equivalents; and (iv) continuously review, supervise, and administer the investment program of the Fund. As applicable and appropriate, and without limiting the generality of the foregoing, the Investment Manager has the power and authority (including the power to sub-delegate) to review, negotiate and execute any and all agreements, letters, instruments, certificates and other documentation necessary to facilitate, effect and manage the purchase, sale and holding of the Fund’s investments.

The Investment Manager agrees that it will discharge its responsibilities under this Agreement subject to the supervision of the Board of Directors and in accordance with (i) the terms hereof; (ii) the Fund’s limited liability company agreement; (iii) the investment objectives, policies, guidelines, and restrictions of the Fund, (iv) the applicable rules and regulations of the Securities and Exchange Commission (the “SEC”), and other federal and state laws; and (v) any policies determined by the Fund’s Board of Directors, all of (i)-(v) hereof as from time to time in effect. In managing the Fund’s portfolio, the Investment Manager will not take any actions with respect to the Fund’s assets that would cause AMG Pantheon Infrastructure Fund, LLC to violate any provisions of the Investment Company Act of 1940, as amended (the “Investment Company Act”), applicable to AMG Pantheon Infrastructure Fund, LLC.

Subject to the prior approval of a majority of the Directors, including a majority of the Directors who are not interested persons of the Fund (“Independent Directors”) and, to the extent it would be required by the Investment Company Act if the Fund were registered under the Investment Company Act and the rules and regulations thereunder (subject to any applicable guidance or interpretation of the Securities and Exchange Commission or its staff and any applicable exemptive orders), by the investors of the Fund, the Investment Manager may, from time to time, delegate to a sub-adviser any of the Investment Manager’s duties under this Agreement, including the management of all or a portion of the assets being managed. In all instances, however, the Investment Manager must oversee the provision of delegated services, the Investment Manager must bear the separate costs of employing any sub-adviser, and no delegation will relieve the Investment Manager of any of its obligations under this Agreement. As used in this Section 2(c), the term “interested persons” has the meaning set forth in the Investment Company Act.

Fees.

Management Fee. For the services provided and the expenses assumed pursuant to this Agreement, the Fund shall pay to the Investment Manager compensation at an annual rate of 1.30%, accrued daily and payable monthly in arrears by the 10th business day of the succeeding month based upon the Fund’s average daily “Managed Assets.” “Managed Assets” means the total assets of the Fund (including any assets attributable to any leverage that may be outstanding) minus the sum of accrued liabilities (other than debt representing financial leverage and the aggregate liquidation preference of any

Expenses.

Other than as specifically indicated in this Agreement, the Investment Manager shall not be required to pay any expenses of the Fund. The Investment Manager shall bear its own operating and overhead expenses attributable to its duties hereunder (such as salaries, bonuses, rent, office and administrative expenses, depreciation and amortization, and auditing expenses). The Fund is not responsible for the overhead expenses of the Investment Manager. The Investment Manager may from time to time agree not to impose all or a portion of its Management Fee otherwise payable under this Agreement and/or undertake to pay or reimburse the Fund for all or a portion of its expenses not otherwise required to be paid by or reimbursed by the Investment Manager. Unless otherwise agreed, any Management Fee reduction or undertaking may be discontinued or modified by the Investment Manager at any time.

The Fund will bear all of the legal and other out-of-pocket expenses incurred in connection with the organization of the Fund and the offering of its units, including (i) all expenses related to the investment program, which include (A) expenses borne (1) through the Fund’s investments in the underlying investment funds (“Investment Funds”) including, without limitation, any fees and expenses charged by the managers of the Investment Funds (such as management fees, performance, carried interests or incentive fees or allocations, monitoring fees, property management fees, and redemption or withdrawal fees), (2) through the Fund’s investments in other investment companies, and (3) through the Fund’s co-investments in portfolio companies; (B) all costs and expenses directly related to portfolio transactions and positions for the Fund’s account, such as direct and indirect expenses associated with the Fund’s investments in Investment Funds, co-investments in portfolio companies and any other investments (whether or not consummated), and enforcing the Fund’s rights in respect of such investments; (C) transfer taxes and premiums; (D) taxes withheld on non-U.S. dividends or other non-U.S. source income; (E) professional fees (including, without limitation, the fees and expenses of consultants, attorneys, and experts of the Fund); and (F) if applicable, brokerage commissions, private placement fees, interest, and commitment fees on loans and debit balances, borrowing charges on securities sold short, dividends on securities sold but not yet purchased and margin fees; (ii) the Management Fee; (iii) all costs and expenses

Fund Transactions.

Other Activities and Investments.

The Investment Manager and its officers and employees shall devote so much of their time to the affairs of the Fund as in the judgment of the Investment Manager the conduct of its business shall reasonably require, and none of the Investment Manager or its affiliates shall be obligated to do or perform any act or thing in connection with the business of the Fund not expressly set forth herein.

The services of the Investment Manager to the Fund are not to be deemed exclusive, and the Investment Manager is free to render similar services to others so long as its services to the Fund are not impaired thereby. To the extent that affiliates of, or other accounts managed by, the Investment Manager invest in Investment Funds or other types of investments that limit the amount of assets and the number of accounts that they will manage or where capacity or access to such investment opportunity is otherwise constrained, the Investment Manager may be required to choose between the Fund and other accounts or affiliated entities in making allocation decisions. The Investment Manager will make allocation decisions in a manner it believes to be equitable to each account. It is recognized that in some cases this may adversely affect the price paid or received by the Fund or the size or position obtainable for or disposed by the Fund. Nothing herein contained in this Section 6 shall be deemed to preclude the Investment Manager or its affiliates from exercising investment responsibility, from engaging directly or indirectly in any other business or from directly or indirectly purchasing, selling, holding, or otherwise dealing with any Investment Funds or co-investments in portfolio companies for the account of any such other business, for their own accounts, for any of their family members or for other clients.

It is understood that any of the investors, Directors, officers, and employees of the Fund may be an investor, director, officer, or employee of, or be otherwise interested in, the Investment Manager, and in any person controlled by or under common control with the Investment Manager, and that the Investment Manager and any person controlled by or under common control with the Investment Manager may have an interest in the Fund. It is also understood that the Investment Manager and any person controlled by or under common control with the Investment Manager may have advisory, management, service, or other contracts with other organizations and persons and may have other interests and business.

Reports and Other Information.

The Fund and the Investment Manager agree to furnish to each other, if applicable, current registration statements, proxy statements, reports to investors, certified copies of their financial statements, and such other information with respect to their affairs as each may reasonably request. The Investment Manager further agrees to furnish to the Fund, if applicable, the same such documents and information pertaining to any sub-adviser as the Fund may reasonably request.

Any records that would be required to be maintained and preserved pursuant to the provisions of Rule 31a-1 and 31a-2 under the Investment Company Act if the Fund were registered under the Investment Company Act will be prepared or maintained by the Investment Manager (or any sub-adviser or administrator) on behalf of the Fund. These records are the property of the Fund and will be surrendered promptly to the Fund on request; provided that the Investment Manager may make and retain copies of such records. The Investment Manager further agrees to preserve these records for the periods prescribed in Rule 31a-2 under the Investment Company Act.

Scope of Liability; Indemnification.

In the absence of willful misfeasance, bad faith, or gross negligence on the part of the Investment Manager, or reckless disregard of its obligations and duties hereunder, the Investment Manager shall not be subject to any liability to the Fund or to any investor of the Fund, for any act or omission in the course of, or connected with, rendering services hereunder. The Fund shall, to the fullest extent permitted by law, indemnify and save harmless the Investment Manager, its affiliates (including any affiliated sub-adviser), and any of their respective partners, members, directors, officers, employees, and investors (the “Indemnitees”) from and against any and all claims, liabilities, damages, losses, costs, and expenses, that are incurred by any Indemnitee and that arise out of or in connection with the performance or non-performance of or by the Indemnitee of any of the Investment Manager’s responsibilities hereunder, provided that an Indemnitee shall be entitled to indemnification hereunder only if the Indemnitee acted in good faith and in a manner the Indemnitee reasonably believed to be in or not opposed to the best interests of the Fund; provided, however, that no Indemnitee shall be indemnified against any liability to the Fund or its investors by reason of willful misfeasance, bad faith, gross negligence or reckless disregard of the Indemnitee’s duties under this Agreement (“disabling conduct”).

Expenses, including reasonable counsel fees incurred by the Indemnitee (but excluding amounts paid in satisfaction of judgments, in compromise, or as fines or penalties), shall be paid from time to time by the Fund in advance of the final disposition of a proceeding upon receipt by the Fund of an undertaking by or on behalf of the Indemnitee to repay amounts so paid to the Fund if it is ultimately determined that indemnification of such expenses is not authorized under this Agreement; provided, however, that (i) the Indemnitee shall provide security considered in the sole discretion of the Fund to be appropriate for such undertaking; (ii) the Fund shall be insured against losses arising

Independent Contractor.

Term; Termination; Renewal.

unless otherwise terminated, this Agreement shall continue in effect until [ , 2027], and from year to year thereafter so long as such continuance is specifically approved at least annually (i) by the Board of Directors or by vote of a majority of the outstanding voting securities of the Fund, and (ii) by vote of a majority of the Directors of the Fund who are not interested persons of the Fund, AMG Pantheon Infrastructure Fund, LLC or the Investment Manager, cast in person at a meeting called for the purpose of voting on such approval;

this Agreement may at any time be terminated on sixty days’ written notice to the Investment Manager either by vote of (i) the Board of Directors of the Fund; (ii) the Board of Directors of AMG Pantheon Infrastructure Fund, LLC; or (iii) a majority of the outstanding voting securities of the Fund;

this Agreement shall automatically terminate in the event of its assignment (as defined in section 2(a)(4) of the Investment Company Act); and

this Agreement may be terminated by the Investment Manager on sixty days’ written notice to the Fund.

Amendment; Modification; Waiver.

Use of the Name “Pantheon.”

Notices.

Governing Law.

Severability.

Track Record.

Counterparts.

Miscellaneous.

No Third Party Beneficiaries.