Exhibit 99.(h)(54)

RULE 12d1-4

FUND OF FUNDS INVESTMENT AGREEMENT

THIS AGREEMENT, dated as of January 19, 2022, among the Calamos Investment Trust, Calamos Long/Short Equity & Dynamic Income Trust, on behalf of themselves and their separate series listed on Schedule A (each, an "Investing Fund"), severally and not jointly, and the investment trusts listed on Schedule A, on behalf of themselves and their respective series also listed on Schedule A, severally and not jointly (each, a "Vanguard Fund" and together with the Investing Funds, the "Funds").

WHEREAS, each Fund is registered with the U.S. Securities and Exchange Commission ("SEC") as an investment company under the Investment Company Act of 1940, as amended, (the "1940 Act");

WHEREAS, Section 12(d)(1)(A) of the 1940 Act limits the extent to which a registered investment company may invest in shares of other registered investment companies, Section 12(d)(1)(8) limits the extent to which a registered open-end investment company, its principal underwriter ("Distributor") or registered brokers or dealers ("Brokers") may knowingly sell shares of such registered investment company to other investment companies, and Section 12(d)(1)(C) limits the extent to which an investment company may invest in the shares of a registered closed-end investment company;

WHEREAS, Rule 12d1-4 under the 1940 Act (the "Rule") permits (i) registered investment companies, such as the Investing Funds, to invest in shares of other registered investment companies, such as the Vanguard Funds, in excess of the limits of Section 12(d)(1)(A) of the 1940 Act, and (ii) registered investment companies, such as the Vanguard Funds, as well as the Distributor and Brokers, knowingly to sell shares of the Vanguard Funds to the Investing Funds in excess of the limits of Section 12(d)(1)(8) of the 1940 Act, subject to compliance with the conditions of the Rule;

WHEREAS, an Investing Fund may, from time to time, invest in shares of one or more Vanguard Funds in excess of the limitations of Section 12(d)(1)(A) in reliance on the Rule; and

WHEREAS, a Vanguard Fund, Distributor, or Broker, from time to time, may knowingly sell shares of one or more Vanguard Funds to an Investing Fund in excess of the limitations of Section 12(d)(1)(8) in reliance on the Rule;

NOW THEREFORE, in accordance with the Rule, the Investing Funds and the Vanguard Fund[s] desire to set forth the following terms pursuant to which the Investing Funds may invest in the Vanguard Funds in reliance on the Rule and the Vanguard Funds, Distributor, or Broker may sell shares of the Vanguard Funds to the Investing Funds in reliance on the Rule.

1.             Terms of Investment

(a) With respect to investments in Vanguard Funds that operate as exchange-traded funds ("Vanguard ETFs"), the Funds note that each Vanguard ETF is designed to accommodate large investments and redemptions, whether from Investing Funds or other investors. Creation and redemption orders for shares of the Vanguard ETFs can only be submitted by Brokers or other participants of a registered clearing agency (collectively, "Authorized Participants") that have entered into an agreement ("Authorized Participant Agreement") with the Vanguard ETFs' distributor to transact in shares of the Vanguard ETFs. The Vanguard ETFs also have policies and procedures (the "Basket Policies") that have been adopted pursuant to Rule 6c-11 under the 1940 Act, which govern creations and redemptions of the Vanguard ETFs' shares. Any creation or redemption order submitted by an Investing Fund through an Authorized Participant will be satisfied pursuant to the Basket Policies and the relevant Authorized Participant Agreement. The Basket Policies include provisions that govern in-kind creations and redemptions, as well as cash transactions. In any event, the Funds generally expect that the Investing Funds will transact in shares in the Vanguard ETFs on the secondary market rather than through direct creation and redemption transactions with the Vanguard ETF. The Funds believe that these material terms regarding an Investing Fund's investment in shares of a Vanguard ETF should assist the Vanguard ETF's investment adviser, the Vanguard Group Inc. ("Vanguard), with making the required findings under the Rule.

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(b) In order to help reasonably address the risk of undue influence on a Vanguard Fund that operates as a mutual fund ("Vanguard Mutual Fund") by an Investing Fund, and to assist Vanguard with making the required findings under the Rule, each Investing Fund and each Vanguard Mutual Fund agree as follows:

(i)             In-kind redemptions. The Investing Fund acknowledges and agrees that, if and to the extent consistent with the Vanguard Mutual Fund's registration statement, as amended from time to time, the Vanguard Mutual Fund may honor any redemption request partially or wholly in-kind.

(ii)            Timing/advance notice of redemptions. The Investing Fund will use reasonable efforts to spread large redemption requests over multiple days or to provide advance notification of redemption requests to the Vanguard Mutual Fund(s), in each case whenever practicable and consistent with the Investing Fund's best interests. The Vanguard Mutual Funds acknowledge and agree that any notification provided pursuant to the foregoing is not a commitment to redeem and constitutes an estimate that may differ materially from the amount, timing and manner in which a redemption request is submitted, if any.

(iii)            Scale of investment. Upon a reasonable request by a Vanguard Mutual Fund, the Investing Fund will provide summary information regarding the anticipated timeline of its investment in the Vanguard Mutual Fund and the scale of its contemplated investments in the Vanguard Mutual Fund.

(c) In order to assist the Investing Fund's investment adviser with evaluating the complexity of the structure and fees and expenses associated with an investment in a Vanguard Fund, each Vanguard Fund shall provide each Investing Fund with information on the fees and expenses of the Vanguard Fund reasonably requested by the Investing Fund with reference to the Rule.

2.             Representations of the Vanguard Funds.

In connection with any investment by an Investing Fund in a Vanguard Fund in excess of the limitations in Section 12(d)(1)(A) or knowing sale of shares by a Vanguard Fund, Distributor, or Broker to an Investing Fund in excess of the limitations in Section 12(d)(1)(B), the Vanguard Fund agrees to: (i) comply with all conditions of the Rule, as interpreted or modified by the SEC or its Staff from time to time, applicable to Vanguard Funds; (ii) comply with its obligations under this Agreement; and (iii) promptly notify the Investing Fund if such Vanguard Fund fails to comply with the Rule with respect to an investment by the Investing Fund, as interpreted or modified by the SEC or its Staff from time to time, or this Agreement.

3.             Representations of the Investing Funds.

In connection with any investment by an Investing Fund in a Vanguard Fund in excess of the limitations in Section 12(d)(1)(A) or knowing sale of Shares by a Vanguard Fund, Distributor, or Broker to an Investing Fund in excess of the limitations in Section 12(d)(1)(B), the Investing Fund agrees to: (i) comply with all conditions of the Rule, as interpreted or modified by the SEC or its Staff from time to time, applicable to Investing Funds; (ii) comply with its obligations under this Agreement; (iii) promptly notify the Vanguard Fund when it has invested in the Vanguard Fund in an amount which exceeds the limitations in Section 12(d)(1)(A); and (iv) promptly notify the Vanguard Fund if such Investing Fund fails to comply with the Rule with respect to its investment in such Vanguard Fund, as interpreted or modified by the SEC or its Staff from time to time, or this Agreement.

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4.             Indemnification.

(a)             Each Investing Fund, severally and not jointly, agrees to hold harmless, indemnify and defend the Vanguard Funds, including any principals, directors or trustees, officers, employees and agents ("Vanguard Agents"), against and from any and all losses, costs, expenses or liabilities incurred by or claims or actions ("Claims") asserted against the Vanguard Funds, including any Vanguard Agents, to the extent such Claims result from (i) a violation or alleged violation by such Investing Fund of any provision of this Agreement or (ii) a violation or alleged violation of the terms and conditions of the Rule, as applicable, in each case by the Investing Fund, its principals, directors or trustees, officers, employees, agents, advisers or if applicable, subadvisers.

(b)             The Vanguard Funds, severally and not jointly, agree to hold harmless, indemnify and defend each Investing Fund, including any principals, directors or trustees, officers, employees and agents ("Investing Fund Agents"), against and from any and all Claims asserted against an Investing Fund, including any Investing Fund Agents, to the extent such Claims result from (i) a violation or alleged violation by such Vanguard Fund of any provision of this Agreement or (ii) a violation or alleged violation of the terms and conditions of the Rule, as applicable, in each case by the Vanguard Fund, its principals, directors or trustees, officers, employees, agents or advisers.

(c)             Any indemnification pursuant to this Section shall include any reasonable counsel fees and expenses incurred in connection with investigating and/or defending the applicable Claims. In any action involving the parties under this Agreement, the parties agree to look solely to the individual series of the Investing Funds or the Vanguard Funds that are involved in the matter in controversy and not to any other series.

5.             Notices

All notices, including all information that either party is required to provide under the terms of this Agreement and the Rule, shall be in writing and shall be delivered by registered or overnight mail, facsimile, or electronic mail to the address for each party specified below.

If to an Investing Fund:   Calamos Family of Funds Attn: General Counsel c/o Calamos Advisors LLC 2020 Calamos Court Naperville, IL 60563 Email: legalnotices@calamos.com   With a Copy to Calamos Compliance Department Email: Compliancedept@calamos.com If to a Vanguard Fund:   ETF Counsel The Vanguard Group, Inc. Legal Department, V26 400 Devon Park Drive Wayne, PA 19087 Fax: (610) 669-6600 Email: 12d1_Notices@vanguard.com

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6.             Term and Termination: Governing Law: Dispute Resolution

(a)             This Agreement shall be effective for the duration of the Vanguard Funds' and the Investing Funds' reliance on the Rule, as interpreted or modified by the SEC or its Staff from time to time. While the terms of the Agreement shall only be applicable to investments in Funds made in reliance on the Rule, as interpreted or modified by the SEC or its Staff from time to time, the Agreement shall continue in effect until terminated pursuant to Section 6(b).

(b)             This Agreement shall continue, in its entirety or with respect to any particular Investing Fund or Vanguard Fund, until terminated in writing by any party upon 60 days' written notice to the other parties. Upon termination of this Agreement, no Investing Fund may purchase additional shares of a Vanguard Fund beyond the Section 12(d)(1)(A) limits in reliance on the Rule. Upon termination of this Agreement with respect to any particular Investing Fund or Vanguard Fund, the parties may not rely on the Rule with respect to any investment by such terminated Investing Fund in shares of Vanguard Funds or investment in shares of such terminated Vanguard Fund by Investing Funds.

(c)             This Agreement will be governed by Pennsylvania law without regard to choice of law principles.

(d)             Any dispute arising out of or related to this Agreement which cannot be resolved through discussions between the parties shall be settled by binding arbitration before a panel of three arbitrators in accordance with and subject to the Commercial Arbitration Rules of the American Arbitration Association then applicable. Unless otherwise agreed upon by the parties, the arbitration hearings will be held in Philadelphia, Pennsylvania.

7.             Miscellaneous

(a)             This Agreement may not be assigned by either party without the prior written consent of the other. In the event either party assigns this Agreement to a third party as provided in this Section, such third party shall be bound by the terms and conditions of this Agreement applicable to the assigning party. Any assignment in contravention of this Section shall be null and void.

(b)             Except as expressly set forth herein, nothing in this Agreement shall confer any rights upon any person or entity other than the parties hereto and their respective successors and permitted assigns.

(c)             This Agreement may be executed in two or more counterparts, each of which shall be deemed an original and all of which together shall constitute one and the same instrument. This Agreement shall become binding when any two or more counterparts thereof, individually or taken together, bear the signatures of both parties hereto. For purposes hereof, a facsimile copy of this Agreement, including the signature pages hereto, shall be deemed an original.

(d)             With the exception of Schedule A, which may be amended via email notification to the contact identified in Section 5 of this Agreement, no amendment, modification, or supplement of any provision of this Agreement will be valid or effective unless made in writing in the manner provided by Section 5 and signed by a duly authorized representative of each party.

(e)             The effectiveness of this Agreement shall be deemed to constitute the termination as of the date first written above of any and all prior agreements between Investing Funds and Vanguard Funds that relates to the investment by any Investing Funds in any Vanguard Funds in reliance on a participation agreement, exemptive order or other arrangement among the parties intended to achieve compliance with Section 12(d)(1) of the 1940 Act (the "Prior Section 12 Agreements"). The parties hereby waive any notice provisions, conditions to termination, or matters otherwise required to terminate such Prior Section 12 Agreements.

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(f) In the case of Calamos Investment Trust, a copy of the Declaration of Trust is on file with the Secretary of The Commonwealth of Massachusetts, and notice is hereby given that no trustee, officer, employee, agent or shareholder of the Investing Funds shall have any personal liability under this Agreement and that this Agreement is binding only upon the assets and property of the applicable Investing Funds.

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IN WITNESS WHEREOF, the parties have executed this Agreement as of the date first written above.

Vanguard Funds
Name of Authorized Signer	Print	Signature
Title: Assistant Secretary	Michael Drayo	/s/ Michael Drayo

Calamos Investment Trust

Calamos Long/Short Equity & Dynamic Income Trust

Name of Authorized Signer	Print	Signature
Title: Vice President & Secretary	J. Christopher Jackson	/s/ J. Christopher Jackson

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SCHEDULE A

List of Funds to Which the Agreement Applies

Investing Funds	Vanguard Funds
The following series of Calamos Investment Trust:
Calamos Market Neutral Income Fund	Vanguard Index Funds   Vanguard S&P 500 ETF (VOO)
Calamos Hedged Equity Fund	Vanguard Index Funds   Vanguard S&P 500 ETF (VOO)
Calamos Phineus Long/Short Fund	Vanguard Index Funds   Vanguard S&P 500 ETF (VOO) Vanguard International Equity Index Funds   Vanguard FTSE Europe ETF (VGK) Vanguard Specialized Funds   Vanguard Real Estate ETF (VNQ)
Calamos Long/Short Equity & Dynamic Income Trust	Vanguard Index Funds Vanguard S&P 500 ETF (VOO) Vanguard International Equity Index Funds Vanguard FTSE Europe ETF (VGK) Vanguard Specialized Funds Vanguard Real Estate ETF (VNQ)

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