# EDGAR Filing Document

**Accession Number:** 0000319676
**File Stem:** 0001133228-26-004865
**Filing Date:** 2026-4
**Character Count:** 34093
**Document Hash:** e06902fd8a989a98c8a99d6b747e325c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001133228-26-004865.hdr.sgml**: 20260408

**ACCESSION NUMBER**: 0001133228-26-004865

**CONFORMED SUBMISSION TYPE**: POS EX

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20260408

**DATE AS OF CHANGE**: 20260408

**EFFECTIVENESS DATE**: 20260408

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Calvert Management Series
- **CENTRAL INDEX KEY:** 0000319676

**ORGANIZATION NAME:**
- **EIN:** 526211999
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** POS EX
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-288593
- **FILM NUMBER:** 26847329

**BUSINESS ADDRESS:**
- **STREET 1:** 2050 M STREET NW
- **CITY:** WASHINGTON
- **STATE:** DC
- **ZIP:** 20036
- **BUSINESS PHONE:** 8002256265

**MAIL ADDRESS:**
- **STREET 1:** 2050 M STREET NW
- **CITY:** WASHINGTON
- **STATE:** DC
- **ZIP:** 20036

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** CALVERT TAX FREE RESERVES
- **DATE OF NAME CHANGE:** 19920703

As filed with the Securities and Exchange Commission on April 8, 2026

1933 Act File No. 333-288593

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, D.C. 20549**

**FORM N-14**

---

| |
|:---|
| **REGISTRATION STATEMENT**<br> **UNDER**<br> **THE SECURITIES ACT of 1933** |
| **PRE-EFFECTIVE AMENDMENT NO.** |
| **POST-EFFECTIVE AMENDMENT NO. 1** |

---

**CALVERT MANAGEMENT SERIES**

**(Exact Name of Registrant as Specified in Charter)**

**2050 M Street NW, Washington, DC 20036**

**(Address of Principal Executive Offices)**

**(202) 238-2200**

**(Registrant's Telephone Number)**

**DEIDRE E. WALSH**

**One Post Office Square, Boston, Massachusetts 02109**

**(Name and Address of Agent for Service)**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

It is proposed that this filing will become effective immediately pursuant to Rule 462(d) under the Securities Act of 1993, as amended.

An indefinite amount of the Registrant's securities have been registered under the Securities Act of 1933 pursuant to Rule 24f-2 under the Investment Company Act of 1940. In reliance upon such Rule, no filing fee is paid at this time.

This Post-Effective Amendment No. 1 ("Amendment") to the Registrant's Registration Statement on Form N-14 (File No. 333-288593) (the "Registration Statement") relates solely to the Calvert Small/Mid-Cap Fund series of the Registrant. Information contained in the Registration Statement relating to any other series of the Registrant is neither amended nor superseded hereby.

**EXPLANATORY NOTE**

The purpose of this Amendment is to file, as an exhibit to the Registration Statement, the opinion of Ropes & Gray LLP supporting the tax matters and consequences to shareholders of the reorganization of Calvert Mid-Cap Fund, a series of Calvert World Values Fund, Inc., with and into Calvert Small/Mid-Cap Fund, a series of the Registrant, as required by Item 16(12) of Form N-14. Accordingly, this Amendment consists only of a facing page, this explanatory note, and Part C of the Registration Statement setting forth the exhibits to the Registration Statement. The Registrant hereby incorporates by reference the Information Statement/Prospectus and Statement of Additional Information filed as Parts A and B, respectively, to Registrant's [Form N-14 on July 9, 2025 (File No. 333-288593)](https://www.sec.gov/Archives/edgar/data/319676/000119312525157144/d17569dn14.htm) and subsequently filed in definitive form pursuant to [Rule 497 on August 8, 2025 (SEC Accession No. 0001193125-25-177074)](https://www.sec.gov/Archives/edgar/data/319676/000119312525177074/d25349d497.htm). This Amendment does not modify any other part of the Registration Statement. There have been no changes to the Information Statement/Prospectus or Statement of Additional Information as filed by the Registrant pursuant to Rule 497 on August 8, 2025.

**PART C - OTHER INFORMATION**

**Item 15. Indemnification**

Article XI, Section 4 of the Registrant's Declaration of Trust provides that the Registrant, out of the Registrant's assets, shall indemnify every person who is or has been a Trustee, officer, employee or agent of the Registrant and every person who serves at the Registrant's request as director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise shall be indemnified by the Registrant to the fullest extent permitted by law against all liabilities and against all expenses reasonably incurred or paid by him in connection with any debt, claim, action, demand, suit, proceeding, judgment, decree, liability or obligation of any kind in which he becomes involved as a party or otherwise or is threatened by virtue of his being or having been a Trustee, officer, employee or agent of the Registrant or of another corporation, partnership, joint venture, trust or other enterprise at the request of the Registrant against amounts paid or incurred by him in the compromise or settlement thereof.

No indemnification shall be provided to any person hereunder against any liabilities to the Registrant or its shareholders adjudicated to have been incurred by reason of willful misfeasance, bad faith, gross negligence, or reckless disregard of the duties involved in the conduct of such person's office.

Article V, Section 1(t) of the Registrant's Declaration of Trust, and Article IX, Section 3 of the Registrant's By-Laws, provide that the Registrant's Trustees are permitted to purchase insurance of any kind, including, without limitation, insurance on behalf of any person who is or was a Trustee, officer, employee or agent of the Trust, or is or was serving at the request of the Trust as a trustee, director, officer, agent or employee of another corporation, partnership, joint venture, trust or other enterprise against any liability asserted against such person and incurred by such person in any such capacity or arising out of such person's status as such.

In addition, indemnification against certain liabilities of the Registrant's trustees and officers and/or the Registrant's administrator, principal underwriter, transfer agent, custodian and other service providers are provided in: (1) Section 5 of the Administrative Services Agreement between the Registrant and Calvert Research and Management; (2) Section 4 of the Master Distribution Agreement between the Registrant and Eaton Vance Distributors, Inc.; (3) Section 14 of the Master Custodian Agreement between the Registrant and State Street Bank and Trust Company; (4) Section 12 of the Securities Lending Authorization Agreement between the Registrant and State Street Bank and Trust Company; and (5) Section 8 of the Administration Agreement between the Registrant and State Street Bank and Trust Company. Generally, such indemnification does not apply to any liabilities by reason of willful misfeasance, bad faith or gross negligence and reckless disregard of duties. These Agreements are incorporated herein by reference to Item 16.

**Item 16. Exhibits (with inapplicable items omitted)** 

&nbsp;&nbsp;&nbsp;&nbsp;(1) [Amended and Restated Declaration of Trust dated September 11, 2018](http://www.sec.gov/Archives/edgar/data/319676/000094039419000112/exhibita_ex-99za.htm) [filed as Exhibit (a) to Post-Effective Amendment No. 105 filed January 28, 2019 (Accession No. 0000940394-19-000112) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/319676/000094039419000112/exhibita_ex-99za.htm)

(2) [Amended and Restated By-Laws of Registrant adopted December 2018](http://www.sec.gov/Archives/edgar/data/319676/000094039419000112/exhibitb_ex-99zb.htm) [filed as Exhibit (b) to Post-Effective Amendment No. 105 filed January 28, 2019 (Accession No. 0000940394-19-000112) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/319676/000094039419000112/exhibitb_ex-99zb.htm)

(3) Not applicable.

(4) Agreement and Plan of Reorganization – Form of Agreement and Plan
 of Reorganization by and among Calvert World Values Fund, Inc., on behalf of its series, Calvert Mid-Cap Fund and Calvert Management Series,
 on behalf of its series, Calvert Small/Mid-Cap Fund, and with respect to Section 10.1 only, Calvert Research and Management, is attached
 as Appendix A to the Information Statement/Prospectus contained in this Registration Statement.

&nbsp;&nbsp;&nbsp;&nbsp;(5) Reference is made to Item 16(a) and 16(b) above.

(6) (a) (1) [Investment Advisory Agreement between Calvert Management Series (on behalf of its separate identified on Schedule A) and Calvert Research and Management dated March 1, 2021 filed as Exhibit (d) to Post-Effective Amendment No. 114 filed April 28, 2021 (Accession No. 0000940394-21-000778) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/319676/000094039421000778/exhibitd_ex99zd.htm)

(2) [Amended and Restated Schedule A effective](http://www.sec.gov/Archives/edgar/data/319676/000094039424000050/exhibitd1b_ex99zd1b.htm) [December 11, 2023](http://www.sec.gov/Archives/edgar/data/319676/000094039424000050/exhibitd1b_ex99zd1b.htm) [to the Investment Advisory Agreement dated March 1, 2021 filed as Exhibit (d)(1)(b) to Post-Effective Amendment No. 69 filed January 25, 2024 (Accession No. 0000940394-24-000050) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/319676/000094039424000050/exhibitd1b_ex99zd1b.htm)

(b) [Investment Sub-Advisory Agreement between Calvert Research and Management and Morgan Stanley Investment Management Company for Calvert Emerging Markets Focused Growth Fund dated December 21, 2022 filed as Exhibit (d)(2) to Post-Effective Amendment No. 124 filed April 12, 2023 (Accession No.0000940394-23-000583) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/319676/000094039423000583/exhibitd2_ex99zd2.htm)

(c) [Investment Sub-Advisory Agreement between Calvert Research and Management and Eaton Vance Advisers International Ltd., for Calvert Global Equity Fund dated September 15, 2023 filed as Exhibit (d)(3) to Post-Effective Amendment No. 129 filed April 28, 2025 (Accession No. 0001076598-25-000031) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/319676/000107659825000031/exhibitd3_ex99zd3.htm)

(d) [Investment Sub-Advisory Agreement between Calvert Research and Management and Eaton Vance Advisers International Ltd., for Calvert Global Small-Cap Equity Fund dated September 15, 2023 filed as Exhibit (d)(4) to Post-Effective Amendment No. 129 filed April 28, 2025 (Accession No.0001076598-25-000031) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/319676/000107659825000031/exhibitd4_ex99zd4.htm)

(7) (a) (1) [Master Distribution Agreement between each registered investment company listed on Schedule A on behalf of each of its series listed on Schedule A, and Eaton Vance Distributors, Inc. effective March 1, 2021 filed as Exhibit (e) to Post-Effective Amendment No. 114 filed April 28, 2021 (Accession No. 0000940394-21-000778) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/319676/000094039421000778/exhibite_ex99ze.htm)

(2) [Amended Schedule A dated January 27, 2026 to Master Distribution Agreement effective March 1, 2021 filed as Exhibit (e)(1)(b) to Post-Effective Amendment No. 60 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 27, 2026 (Accession No. 0001133228-26-000677) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000113322826000677/crisi-efp22166_ex99ze1b.htm)

(8) [Form of Deferred Compensation Agreement filed as Exhibit (f) to Post-Effective Amendment No. 89 of Calvert Social Investment Fund (File Nos. 002-75106, 811-03334) filed January 30, 2017 (Accession No. 0000940394-17-000162) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/356682/000094039417000162/exhibitf_ex99zf.htm)

(9) (a) (1) [Master Custodian Agreement between Calvert Funds and State Street Bank and Trust Company dated December 1, 2000 filed as Exhibit (g) to Post-Effective Amendment No. 65 of Calvert Variable Trust, Inc. (formerly Calvert Variable Products, Inc.) (File Nos. 002-90309, 811-04000) filed January 30, 2009 (Accession No. 0001121624-09-000003) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/743773/000074377309000003/smfexhibitg-custagrmt.htm)

(2) [Amendment is dated as of June 3, 2020 to Master Custodian Agreement between Calvert Funds and State Street Bank and Trust Company dated December 1, 2000 filed as Exhibit (g)(2)](http://www.sec.gov/Archives/edgar/data/701039/000094039421000100/exhibitg2_ex99zg2.htm) [to Post-Effective Amendment No. 122 of The Calvert Fund (File Nos. 002-76510, 811-03416) filed January 27, 2021 (Accession No. 0000940394-21-000100) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/701039/000094039421000100/exhibitg2_ex99zg2.htm)

&nbsp;&nbsp;&nbsp;&nbsp;(10) (a) (1) [Master Distribution Plan for Class A Shares, as adopted December 31, 2016 filed as Exhibit (m)(1) to Post-Effective Amendment No. 89 of Calvert Social Investment Fund (File Nos. 002-75106, 811-03334) filed January 30, 2017 (Accession No. 0000940394-17-000162) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/356682/000094039417000162/exhibitm1_ex99zm1.htm)

(2) [Amended Schedule A dated January 27, 2026 to the Master Distribution Plan for Class A shares adopted December 31, 2016 filed as Exhibit (m)(1)(b) to Post-Effective Amendment No. 60 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 27, 2026 (Accession No. 0001133228-26-000677) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000113322826000677/crisi-efp22166_ex99zm1b.htm)

(b) (1) [Master Distribution Plan for Class C shares filed as Exhibit (m)(3) to Post-Effective Amendment No. 89 of Calvert Social Investment Fund (File Nos. 002-75106, 811-03334) filed January 30, 2017 (Accession No. 0000940394-17-000162) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/356682/000094039417000162/exhibitm2_ex99zm2.htm)

(2) [Amended Schedule A dated January 27, 2026 to the Master Distribution Plan for Class C shares adopted December 31, 2016 filed as Exhibit (m)(2)(b) to Post-Effective Amendment No. 60 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 24, 2025 (Accession No. 0001133228-26-000677) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000113322826000677/crisi-efp22166_ex99zm2b.htm)

(c) (1) [Amended and Restated Multiple Class Plan for Calvert Funds effective January 25, 2019 filed as Exhibit (n) to Post-Effective Amendment No. 95 of Calvert Social Investment Fund (File Nos. 002-75106, 811-03334) filed January 28, 2019 (Accession No. 0000940394-19-000110) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/356682/000094039419000110/exhibitn_ex-99zn.htm)

(2) [Amended Schedule A dated January 27, 2026 to the Amended and Restated Multiple Class Plan for Calvert Funds effective January 25, 2019 filed as Exhibit (n)(1)(b) to Post-Effective Amendment No. 60 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 27, 2026 (Accession No. 0001133228-26-000677) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000113322826000677/crisi-efp22166_ex99zn1b.htm)

(11) [Consent of Internal Counsel dated July 9, 2025 filed July 9, 2025 (Accession No. 0001193125-25-157144) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/319676/000119312525157144/d17569dex9914.htm)

(12) [Opinion of Ropes & Gray LLP with respect to tax matters, dated September 15, 2025, filed herewith.](cms-efp23965_ex9912.htm)

(13) (a) (1) [Administrative Services Agreement between Calvert Research and Management and each registered investment company listed on Appendix A on behalf of each of its series listed on Appendix A, effective March 1, 2021 filed as Exhibit (h)(1) to Post-Effective Amendment No. 114 filed April 28, 2021 (Accession No. 0000940394-21-000778) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/319676/000094039421000778/exhibith1_ex99zh1.htm)

(2) [Amended Appendix A dated](http://www.sec.gov/Archives/edgar/data/319676/000094039423000583/exhibith1b_ex99zh1b.htm) [April 12, 2023](http://www.sec.gov/Archives/edgar/data/319676/000094039423000583/exhibith1b_ex99zh1b.htm) [to the Administrative Services Agreement effective March 1, 2021 filed as Exhibit (h)(1)(b) to Post-Effective Amendment No. 124 filed April 12, 2023 (Accession No. 0000940394-23-000583) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/319676/000094039423000583/exhibith1b_ex99zh1b.htm)

(b) (1) [Transfer Agency and Service Agreement between Calvert Funds listed on Schedule A and DST Asset Manager Solutions, Inc., dated July 1, 2019 filed as Exhibit (h)(2) to Post-Effective Amendment No. 63 of Calvert World Values Fund, Inc. (File Nos. 033-45829, 811-06563) filed September 27, 2019 (Accession No. 0000940394-19-001297) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/884110/000094039419001297/exhibith2_ex-99zh2.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2) [Amendment No. 1 effective as of October 2, 2024 to the Transfer Agency and Service Agreement dated as of July 1, 2019 filed as Exhibit (h)(2)(b) to Post-Effective Amendment No. 60 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 27, 2026 (Accession No. 0001133228-26-000677) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000113322826000677/crisi-efp22166_ex99zh2b.htm)

(3) [Amendment effective as of December 20, 2024 to the Transfer Agency and Service Agreement dated as of July 1, 2019 filed as Exhibit (h)(2)(b) to Post-Effective Amendment No. 59 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 24, 2025 (Accession No. 0000940394-25-000047) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000094039425000047/exhibith2b_ex99zh2b.htm)

(c) [Sub-Transfer Agency Support Services Agreement between Eaton Vance Management and each open-end investment company listed on Appendix A dated December 1, 2017 filed as Exhibit (h)(3) to Post-Effective Amendment No. 93 of Calvert Social Investment Fund (File Nos. 002-75106, 811-03334) filed January 29, 2018 (Accession No. 0000940394-18-000114) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/356682/000094039418000114/exhibith3_ex-99zh3.htm)

(d) (1) [Expense Reimbursement Agreement dated December 31, 2016 as amended March 6, 2019 and March 3, 2021 between Calvert Research and Management and each Trust and/or Corporation (on behalf of certain of their series) listed on Amended Schedule A filed as Exhibit (h)(4)(a) to Post-Effective Amendment No. 114 filed April 28, 2021 (Accession No. 0000940394-21-000778) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/319676/000094039421000778/exhibith4a_ex99zh4a.htm)

(2) [Amended Schedule A dated February 1, 2026 to the Expense Reimbursement Agreement dated December 31, 2016 as amended March 6, 2019 and March 3, 2021 filed as Exhibit (h)(4)(b) to Post-Effective Amendment No. 60 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 27, 2026 (Accession No. 0001133228-26-000677) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000113322826000677/crisi-efp22166_ex99zh4b.htm)

(e) [Form of Fund of Funds Investment Agreement dated January 19, 2022 filed as Exhibit (h)(5) to Post-Effective Amendment No. 119 filed April 28, 2022 (Accession No. 0000940394-22-000782) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/319676/000094039422000782/exhibith5_ex99zh5.htm)

(g) [Expense Reimbursement Agreement](http://www.sec.gov/Archives/edgar/data/701039/000094039423000083/exhibith6_ex99zh6.htm) [for Cash Sweep dated April 26, 2022 between Calvert Research and Management and each Trust and/or Corporation listed on Schedule A filed as Exhibit (h)(6) to Post-Effective Amendment No. 127 of The Calvert Fund (File Nos. 002-76510, 811-03416) filed January 26, 2023 (Accession No. 0000940394-23-000083) and incorporated herein by reference.](http://www.sec.gov/Archives/edgar/data/701039/000094039423000083/exhibith6_ex99zh6.htm)

(14) [Consents of Independent Registered Public Accounting Firm dated July 9, 2025 filed July 9, 2025 (Accession No. 0001193125-25-157144) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/319676/000119312525157144/d17569dex9914.htm)

(15) Not applicable.

(16) (a) [Power of Attorney for Registrant's Trustees/Directors dated January 1, 2026 filed as Exhibit (q)(1) to Post-Effective Amendment No. 60 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 27, 2026 (Accession No. 0001133228-26-000677) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000113322826000677/crisi-efp22166_ex99zq1.htm)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) [Secretary's Certificate dated December 2, 2025 filed as Exhibit (q)(2) to Post-Effective Amendment No. 60 of Calvert Responsible Index Series, Inc. (File Nos. 333-34122, 811-09877) filed January 27, 2026 (Accession No. 0001133228-26-000677) and incorporated herein by reference.](https://www.sec.gov/Archives/edgar/data/1105446/000113322826000677/crisi-efp22166_ex99zq2.htm)

(17) None.

**Item 17. Undertakings**

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1. The undersigned Registrant agrees that prior to any public reoffering of the securities registered through the use of a prospectus which is a part of this registration statement by any person or party who is deemed to be an underwriter within the meaning of Rule 145(c) under the Securities Act of 1933, the reoffering prospectus will contain the information called for by the applicable registration form for reofferings by persons who may be deemed underwriters, in addition to the information called for by the other items of the applicable form.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2. The undersigned Registrant agrees that every prospectus that is filed under paragraph (1) above will be filed as a part of an amendment to the registration statement and will not be used until the amendment is effective, and that, in determining any liability under the Securities Act of 1933, each post-effective amendment shall be deemed to be a new registration statement for the securities offered therein, and the offering of the securities at that time shall be deemed to be the initial bona fide offering of them.

**SIGNATURES**

Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certified that it has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized in the City of Boston, and the Commonwealth of Massachusetts, on April 8, 2026.

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| | |
|:---|:---|
| CALVERT MANAGEMENT SERIES | CALVERT MANAGEMENT SERIES |
| By: | Von M. Hughes\* |
|  | Von M. Hughes, President |

---

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed below by the following persons in the capacities indicated on April 8, 2026.

---

| | |
|:---|:---|
| Signature | Title |
| Von M. Hughes\* | President and Trustee |
| Von M. Hughes |  |
| James F. Kirchner\* | Treasurer (Principal Financial and Accounting Officer) |
| James F. Kirchner |  |

---

---

| | | | |
|:---|:---|:---|:---|
| Signature | Title | Signature | Title |
| Karen C. Fang\* | Trustee | Edward Ramos\* | Trustee |
| Karen C. Fang |  | Edward Ramos |  |
| Miles D. Harper, III\* | Trustee | Anthony A. Williams\* | Trustee |
| Miles D. Harper, III |  | Anthony A. Williams |  |
| Kim M. Keenan\* | Trustee | Carlton M. Waterhouse \* | Trustee |
| Kim M. Keenan |  | Carlton M. Waterhouse |  |

---

---

| | |
|:---|:---|
| \*By: | /s/ Deidre E. Walsh |
|  | Deidre E. Walsh *(As attorney-in-fact)* |

---

**EXHIBIT INDEX**

The following exhibits are filed as part of this Post-Effective Amendment to the Registration Statement pursuant to Rule 483 of Regulation C.

Exhibit No. Description <br>(12) [Opinion of Ropes & Gray LLP with respect to tax matters, dated September 15, 2025](cms-efp23965_ex9912.htm)

## Exhibit 99.12

**Exhibit (12)**

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| | | |
|:---|:---|:---|
| &nbsp;&nbsp;![](img001.jpg) | ROPES & GRAY LLP<br> 1211 AVENUE OF THE AMERICAS<br> NEW YORK, NY 10036-8704<br> WWW.ROPESGRAY.COM |  |
|  |  | September 15, 2025 |

---

Calvert Mid-Cap Fund

Calvert World Values Fund, Inc.

2050 M Street NW

Washington, DC 20036-3598

Calvert Small/Mid-Cap Fund

Calvert Management Series

2050 M Street NW

Washington, DC 20036-3598

Ladies and Gentlemen:

We have acted as counsel in connection with the Agreement and Plan of Reorganization (the "<u>Agreement</u>"), dated September 9, 2025, between Calvert World Values Fund, Inc., a Maryland corporation, ("<u>CWVF</u>") on behalf of its series, Calvert Mid-Cap Fund (the "<u>Target Fund"</u>), Calvert Management Series, a Massachusetts business trust, ("<u>CMS</u>") on behalf of its series, Calvert Small/Mid-Cap Fund (the "<u>Acquiring Fund,</u>" and together with the Target Fund, the "<u>Funds</u>," and each a "<u>Fund</u>"), and solely for purposes of Section 10 thereto, Calvert Research and Management. The Agreement describes a proposed transaction to occur on the date of this letter, pursuant to which the Acquiring Fund will acquire all of the assets of the Target Fund in exchange for shares of beneficial interest in the Acquiring Fund ("<u>Merger Shares</u>") and the assumption by the Acquiring Fund of all of the liabilities of the Target Fund, following which such Merger Shares received by the Target Fund will be distributed by the Target Fund to its shareholders in liquidation and termination of the Target Fund (the "<u>Reorganization</u>"). This opinion as to certain U.S. federal income tax consequences of the Reorganization is furnished to you pursuant to Section 7.3 of the Agreement. Capitalized terms not defined herein are used herein as defined in the Agreement.

The Target Fund is a series of CWVF, which is registered under the Investment Company Act of 1940, as amended, (the "<u>1940 Act</u>") as an open-end management investment company. Shares of the Target Fund are redeemable at net asset value at each shareholder's option. The Target Fund has elected to be a regulated investment company for U.S. federal income tax purposes under Section 851 of the Internal Revenue Code of 1986, as amended (the "<u>Code</u>").

The Acquiring Fund is a series of CMS, which is registered under the 1940 Act as an open-end management investment company. Shares of the Acquiring Fund are redeemable at net asset value at each shareholder's option. The Acquiring Fund has elected to be a regulated investment company for U.S. federal income tax purposes under Section 851 of the Code.

September 15, 2025

For purposes of this opinion, we have considered the Agreement, the combined Information Statement/Prospectus dated August 8, 2025, and such other items as we have deemed necessary to render this opinion. In addition, each Fund has provided us with a letter dated as of the date hereof (collectively, the "<u>Representation Letters</u>"), representing as to certain facts, occurrences and information upon which such Fund has indicated that we may rely in rendering this opinion (whether or not contained or reflected in the documents and items referred to above).

In reviewing the foregoing materials, we have assumed, with your permission, the authenticity of original documents, the accuracy of copies, the genuineness of signatures, the legal capacity of signatories, and the proper execution of documents. We have further assumed that (i) all parties to the Agreement and any other documents examined by us have acted, and will act, in accordance with the terms of the Agreement and documents, and that the Reorganization will be consummated pursuant to the terms and conditions set forth in the Agreement without the waiver or modification of any such terms and conditions; (ii) all representations contained in the Agreement, as well as those representations contained in the Representation Letters, are true and complete; and (iii) any representation made in any of the documents referred to herein "to the best of the knowledge" of any person or party is true without regard to such qualification.

Based on and subject to the foregoing and subject to the final paragraph hereof, we are of the opinion that, for U.S. federal income tax purposes:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i) The Reorganization will constitute a "reorganization" within the meaning of Section 368(a)(1) of the Code, and the Target Fund and the Acquiring Fund will each be "a party to a reorganization" within the meaning of Section 368(b) of the Code.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii) Under Section 1032 of the Code, the Acquiring Fund will not recognize gain or loss upon the receipt of assets of the Target Fund in exchange for Merger Shares and the assumption by the Acquiring Fund of all of the liabilities of the Target Fund.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii) Under Section 362(b) of the Code, the Acquiring Fund's tax basis in the assets of the Target Fund transferred to the Acquiring Fund in the Reorganization will be the same as the Target Fund's tax basis in such assets immediately prior to the Reorganization, increased by any gain or decreased by any loss required to be recognized as described in (v) below.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv) Under Section 1223(2) of the Code, the Acquiring Fund's holding period in each asset received from the Target Fund in the Reorganization, other than any asset with respect to which gain or loss is required to be recognized as described in (v) below, will include the period during which such asset was held or treated for U.S. federal income tax purposes as being held by the Target Fund.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(v) Under Sections 361 and 357 of the Code, the Target Fund will not recognize gain or loss upon the transfer of all of its assets to the Acquiring Fund in exchange for the Merger Shares and the assumption by the Acquiring Fund of all of the liabilities of the Target Fund, or upon the distribution of the Merger Shares by the Target Fund to its shareholders in liquidation

September 15, 2025

thereof, except for (A) any gain or loss recognized on (1) "Section 1256 contracts" as defined in Section 1256(b) of the Code or (2) stock in a "passive foreign investment company" as defined in Section 1297(a) of the Code, and (B) any other gain or loss required to be recognized by reason of the Reorganization (1) as a result of the closing of the tax year of the Target Fund, (2) upon the termination of a position, or (3) upon the transfer of such asset regardless of whether such a transfer would otherwise be a nontaxable transaction under the Code.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(vi) Under Section 354 of the Code, the shareholders of the Target Fund will not recognize gain or loss upon the exchange of their Target Fund shares for the Merger Shares in the Reorganization (including fractional shares to which they may be entitled).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(vii) Under Section 358 of the Code, the aggregate tax basis of the Merger Shares that a Target Fund shareholder receives in the Reorganization (including fractional shares to which they may be entitled) will be the same as the aggregate tax basis of Target Fund shares exchanged therefor.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(viii) Under Section 1223(1) of the Code, a Target Fund shareholder's holding period for the Merger Shares received (including fractional shares to which they may be entitled) in the Reorganization will include the shareholder's holding period for Target Fund shares exchanged therefor, provided the shareholder held such Target Fund shares as capital assets on the date of the exchange.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ix) The Acquiring Fund will succeed to and take into account the items of the Target Fund described in Section 381(c) of the Code, subject to the conditions and limitations specified in Sections 381, 382, 383 and 384 of the Code and the U.S. Treasury Regulations thereunder.

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September 15, 2025

No ruling has been or will be obtained from the U.S. Internal Revenue Service (the "<u>IRS</u>") as to the subject matter of this opinion and there can be no assurance the IRS or a court of law will concur with the opinion set forth above. Our opinion is based on the Code, U.S. Treasury Regulations, IRS rulings, judicial decisions, and other applicable authority, all as in effect on the date of this opinion. The legal authorities on which this opinion is based may be changed at any time. Any such changes may be retroactively applied and could modify the opinions expressed above. We undertake no obligation to update or supplement this opinion to reflect any such changes that may occur.

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| Very truly yours, |
| /s/ Ropes & Gray LLP |
| Ropes & Gray LLP |

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