# EDGAR Filing Document

**Accession Number:** 0001576885
**File Stem:** 0001628280-26-021418
**Filing Date:** 2026-3
**Character Count:** 21606
**Document Hash:** 5651ff010b96e56b1ed0573e48cfcf76
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001628280-26-021418.hdr.sgml**: 20260326

**ACCESSION NUMBER**: 0001628280-26-021418

**CONFORMED SUBMISSION TYPE**: S-8

**PUBLIC DOCUMENT COUNT**: 14

**REFERENCES 429**: 333-257666

**REFERENCES 429**: 333-263947

**REFERENCES 429**: 333-270902

**REFERENCES 429**: 333-278267

**REFERENCES 429**: 333-286176

**FILED AS OF DATE**: 20260326

**DATE AS OF CHANGE**: 20260326

**EFFECTIVENESS DATE**: 20260326

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Acumen Pharmaceuticals, Inc.
- **CENTRAL INDEX KEY:** 0001576885
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 364108129
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-8
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-294641
- **FILM NUMBER:** 26798230

**BUSINESS ADDRESS:**
- **STREET 1:** 1210-1220 WASHINGTON STREET
- **STREET 2:** SUITE 210
- **CITY:** NEWTON
- **STATE:** MA
- **ZIP:** 02465
- **BUSINESS PHONE:** 617-344-4190

**MAIL ADDRESS:**
- **STREET 1:** 1210-1220 WASHINGTON STREET
- **STREET 2:** SUITE 210
- **CITY:** NEWTON
- **STATE:** MA
- **ZIP:** 02465

**As filed with the Securities and Exchange Commission on March 26, 2026** 

**Registration No. 333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;** 

**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

**FORM S-8** 

**REGISTRATION STATEMENT** 

***UNDER***

***THE SECURITIES ACT OF 1933***

**Acumen Pharmaceuticals, Inc.** 

**(Exact name of registrant as specified in its charter)** 

---

| | |
|:---|:---|
| **Delaware** | **36-4108129** |
| **(State or other jurisdiction of**<br>**incorporation or organization)** | **(I.R.S. Employer**<br>**Identification No.)** |

---

**1210-1220 Washington St., Suite 210** 

**Newton, MA 02465** 

**(617) 344-4190** 

**(Address of principal executive offices, including zip code)** 

**Acumen Pharmaceuticals, Inc. 2021 Equity Incentive Plan** 

**Acumen Pharmaceuticals, Inc. 2021 Employee Stock Purchase Plan** 

**(Full titles of the plans)** 

**Daniel O'Connell** 

**Chief Executive Officer** 

**Acumen Pharmaceuticals, Inc.** 

**1210-1220 Washington St., Suite 210** 

**Newton, MA 02465** 

**(617) 344-4190** 

**(Name, address and telephone number, including area code, of agent for service)** 

***Copies to:***

---

| | |
|:---|:---|
| **Thomas J. Danielski, Esq.** | **Derek Meisner** |
| **Ropes & Gray LLP** | **Chief Legal Officer** |
| **800 Boylston Street** | **Acumen Pharmaceuticals, Inc.** |
| **Boston, MA 02199** | **1210-1220 Washington St., Suite 210** |
| **(617) 951-7000** | **Newton, MA 02465** |
|  | **(617) 344-4190**  |

---

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

---

| | | | |
|:---|:---|:---|:---|
| Large accelerated filer | ☐ | Accelerated filer | ☐ |
| Non-accelerated filer | ☒ | Smaller reporting company | ☒ |
| | | Emerging growth company | ☒ |

---

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

------

**EXPLANATORY NOTE** 

**REGISTRATION OF ADDITIONAL SHARES** 

Acumen Pharmaceuticals, Inc. (the "***Registrant***") is filing this Registration Statement on Form S-8 with the Securities and Exchange Commission (the "***Commission***") for the purpose of registering (i) 3,028,768 additional shares of its common stock under the 2021 Equity Incentive Plan (the "***2021 Plan***"), pursuant to the provisions of the 2021 Plan providing for an automatic increase in the number of shares of common stock reserved and available for issuance under the 2021 Plan on January 1, 2026, (ii) 29,069 additional shares of its common stock under the 2021 Plan pursuant to the provisions of the 2021 Plan providing that shares subject to outstanding stock options or other stock awards that were granted under the Registrant's 2013 Amended and Restated Stock Performance Plan (the "***Prior Plan***") that terminate or expire prior to exercise or settlement, are settled in cash, are forfeited or repurchased because of the failure to vest, or are reacquired or withheld to satisfy a tax withholding obligation or the purchase or exercise price in accordance with the terms of the Prior Plan become available for issuance under the 2021 Plan, and (iii) 605,754 additional shares of its common stock under the 2021 Employee Stock Purchase Plan (the "***2021 ESPP***," and together with the 2021 Plan the "***Plans***"), pursuant to the provisions of the 2021 ESPP providing for an automatic increase in the number of shares of common stock reserved and available for issuance under the 2021 ESPP on January 1, 2026. Pursuant to General Instruction E to Form S-8, the Registrant incorporates by reference, except to the extent supplemented, amended or superseded by the information set forth herein, into this Registration Statement the entire contents of its Registration Statements on Form S-8 (File No. 333-257666) filed with the Commission on July 2, 2021, Form S-8 (File No. 333-263947) filed with the Commission on March 29, 2022, Form S-8 (File No. 333-270902) filed with the Commission on March 28, 2023, Form S-8 (File No. 333-278267) filed with the Commission on March 27, 2024 and Form S-8 (File No. 333-286176) filed with the Commission on March 27, 2025.

------

**PART II** 

**INFORMATION REQUIRED IN REGISTRATION STATEMENT** 

**ITEM 8. EXHIBITS** 

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| | | **Incorporated by Reference** | **Incorporated by Reference** | **Incorporated by Reference** | **Incorporated by Reference** |
|<br>**Exhibit**<br>**Number** | **Description** | **Schedule<br>Form** | **File Number** | **Exhibit** | **Filing Date** |
| 3.1 | <u>[Amended and Restated Certificate of Incorporation of the Registrant.](https://www.sec.gov/Archives/edgar/data/1576885/000157688523000039/active_136401491x1xacume.htm)</u> | 8-K | 001-40551 | 3.1 | June 8, 2023 |
| 3.2 | <u>[Amended and Restated Bylaws of the Registrant.](https://www.sec.gov/Archives/edgar/data/1576885/000157688523000008/abos-20230309xexx31.htm)</u> | 8-K | 001-40551 | 3.1 | March 15, 2023 |
| 5.1\* | <u>[Opinion of Ropes & Gray LLP.](exhibit51s-82026.htm)</u> |  |  |  |  |
| 23.1\* | <u>[Consent of Ropes & Gray LLP (included in Exhibit 5.1).](exhibit51s-82026.htm)</u> |  |  |  |  |
| 23.2\* | <u>[Consent of Ernst & Young, LLP, independent registered public accounting firm.](exhibit232s-82026.htm)</u> |  |  |  |  |
| 24.1\* | <u>[Power of Attorney (included on the signature page of this Form S-8).](#iea2dd4ff16264776bca12e02ee21d8e8_13)</u> |  |  |  |  |
| 99.1 | <u>[2021 Equity Incentive Plan and Forms of Option Grant Notice and Agreement, Exercise Notice, Early Exercise Notice and Restricted Stock Award Notice.](https://www.sec.gov/Archives/edgar/data/1576885/000119312521198037/d104413dex102.htm)</u> | S-1/A | 333-256945 | 10.2 | June 24, 2021 |
| 99.2 | <u>[2021 Employee Stock Purchase Plan](https://www.sec.gov/Archives/edgar/data/1576885/000119312521198037/d104413dex104.htm)</u> | S-1/A | 333-256945 | 10.4 | June 24, 2021 |
| 107\* | <u>[Filing Fee Table](exfilingfeess-8.htm)</u>  |  |  |  |  |

---

__________________

\*Filed herewith.

------

**SIGNATURES** 

Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Newton, Commonwealth of Massachusetts, on March 26, 2026.

---

| | |
|:---|:---|
| **ACUMEN PHARMACEUTICALS, INC.** | **ACUMEN PHARMACEUTICALS, INC.** |
| By: | /s/ Daniel O'Connell |
|  | Daniel O'Connell |
|  | *Chief Executive Officer* |

---

**POWER OF ATTORNEY** 

**KNOW ALL PERSONS BY THESE PRESENTS**, that each person whose signature appears below constitutes and appoints Daniel O'Connell, William Matthew Zuga and Derek Meisner, and each one of them, as his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in their name, place or stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

---

| | | |
|:---|:---|:---|
| **Signature** | **Title** | **Date** |
| /s/ Daniel O'Connell | Chief Executive Officer and Director | March 26, 2026 |
| Daniel O'Connell | *(Principal Executive Officer)* | March 26, 2026 |
| /s/ William Matthew Zuga | Chief Financial Officer and Chief Business Officer | March 26, 2026 |
| William Matthew Zuga | *(Principal Financial and Accounting Officer)* | March 26, 2026 |
| /s/ Kimberlee C. Drapkin | Director | March 26, 2026 |
| Kimberlee C. Drapkin | Director | March 26, 2026 |
| /s/ Nathan B. Fountain | Director | March 26, 2026 |
| Nathan B. Fountain, M.D. | Director | March 26, 2026 |
| /s/ George Golumbeski | Director | March 26, 2026 |
| George Golumbeski, Ph.D. | Director | March 26, 2026 |
| /s/ Jeffrey L. Ives | Director | March 26, 2026 |
| Jeffrey L. Ives, PhD | Director | March 26, 2026 |
| /s/ Derrell D. Porter | Director | March 26, 2026 |
| Derrell D. Porter, M.D. | Director | March 26, 2026 |
| /s/ Sean Stalfort | Director | March 26, 2026 |
| Sean Stalfort | Director | March 26, 2026 |
| /s/ Laura Stoppel | Director | March 26, 2026 |
| Laura Stoppel, PhD | Director | March 26, 2026 |

---

## Ex-Filing

?xml version='1.0' encoding='ASCII'? EX-FILING FEES

---

| |
|:---|
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Calculation of Filing Fee Tables**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **S-8**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Acumen Pharmaceuticals, Inc.**  |

---

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Type**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Class Title**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Calculation Rule**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount Registered**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Proposed Maximum Offering Price Per Unit**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Maximum Aggregate Offering Price**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Rate**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount of Registration Fee**  |
| 1 | Equity | Common stock, $0.0001 par value per share, reserved for future issuance pursuant to the Registrant's 2021 Equity Incentive Plan | Other | 3057837 | $2.60 | $7950376.20 | 0.0001381 | $1097.95 |
| 2 | Equity | Common stock, $0.0001 par value per share, reserved for future issuance pursuant to the Registrant's 2021 Employee Stock Purchase Plan | Other | 605754 | $2.60 | $1574960.40 | 0.0001381 | $217.50 |
| Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: |  | $9525336.60  |  | $1315.45  |
| Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  |  |  |  | $0.00  |
| Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  |  |  |  | $1315.45  |

---

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Offering Note** <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>1</sup> (a) Pursuant to Rule 416(a) promulgated under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement shall also cover any additional shares of common stock of Acumen Pharmaceuticals, Inc. (the "Registrant") that become issuable under the Registrant's 2021 Equity Incentive Plan (the "2021 Plan") and the Registrant's 2021 Employee Stock Purchase Plan (the "2021 ESPP") by reason of any stock dividend, stock split, recapitalization, or other similar transaction effected that results in an increase to the number of outstanding shares of the Registrant's common stock, as applicable. (b) Represents (i) 3,028,768 shares of common stock that were added to the shares reserved for future issuance under the 2021 Plan on January 1, 2026, pursuant to an evergreen provision contained in the 2021 Plan and (ii) 29,069 shares of common stock that were added to the shares reserved for future issuance under the 2021 Plan as a result of forfeited options outstanding under the Registrant's 2013 Amended and Restated Stock Performance Plan (the "Prior Plan"). Pursuant to the evergreen provision contained in the 2021 Plan, the number of shares reserved for issuance under the 2021 Plan will automatically increase on January 1 of each year for a period of 10 years, beginning on January 1, 2022 and continuing through (and including) January 1, 2031, in an amount equal to 5% of the total number of shares of the Registrant's common stock outstanding on December 31 of the immediately preceding year, except that, before the date of any such increase, the Registrant's board of directors may determine that the increase for such year will be a lesser number of shares. Further, the 2021 Plan provides that shares subject to outstanding stock options or other stock awards that were granted under the Prior Plan that terminate or expire prior to exercise or settlement, are settled in cash, are forfeited or repurchased because of the failure to vest, or are reacquired or withheld to satisfy a tax withholding obligation or the purchase or exercise price in accordance with the terms of the Prior Plan become available for issuance under the 2021 Plan. (c) Estimated in accordance with Rules 457(c) and 457(h) solely for the purpose of calculating the registration fee on the basis of $2.60 per share, which is the average of the high and low selling prices per share of the Registrant's common stock on March 24, 2026 as reported on the Nasdaq Global Select Market.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>2</sup> (a) See Note 1(a). (b) Represents shares of common stock that were added to the shares reserved for future issuance under the 2021 ESPP on January 1, 2026, pursuant to an evergreen provision contained in the 2021 ESPP. Pursuant to such provision, the number of shares reserved for issuance under the 2021 ESPP will automatically increase on January 1 of each year for a period of 10 years, beginning on January 1, 2022 and continuing through (and including) January 1, 2031, by the lesser of (a) 1% of the total number of shares of the Registrant's common stock outstanding on December 31 of the immediately preceding year and (b) 800,000 shares, except that, before the date of any such increase, the Registrant's board of directors may determine that the increase for such year will be less than the amount set forth in clauses (a) and (b). (c) Estimated in accordance with Rules 457(c) and 457(h) solely for the purpose of calculating the registration fee. The offering price per share and the aggregate offering price are based upon $2.60, which is the average of the high and low selling prices per share of the Registrant's common stock on March 24, 2026 as reported on the Nasdaq Global Select Market.

---

| |
|:---|
| |
| **Rule 457(p)** |
| Fee Offset Claims |
| Fee Offset Sources |

---

## Exhibit 5.1

**Exhibit 5.1**

---

| | |
|:---|:---|
| ![image_0a.jpg](image_0a.jpg) | ROPES & GRAY LLP<br>PRUDENTIAL TOWER<br>800 BOYLSTON STREET<br>BOSTON, MA 02199-3600<br>WWW.ROPESGRAY.COM |

---

March 26, 2026

Acumen Pharmaceuticals, Inc.

1210-1220 Washington St., Suite 210

Newton, MA 02465

Ladies and Gentlemen:

This opinion is furnished to you in connection with the registration statement on Form S-8 (the "Registration Statement") filed by Acumen Pharmaceuticals, Inc., a Delaware corporation (the "Company"), with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the "Securities Act"), for the registration of 3,663,591 shares of the common stock, par value $0.0001 per share, of the Company (the "Shares"). The Shares are issuable under the Company's 2021 Equity Incentive Plan and 2021 Employee Stock Purchase Plan (each, a "Plan," and collectively, the "Plans").

We are familiar with the actions taken by the Company in connection with the adoption of the Plans. We have examined such certificates, documents and records and have made such investigation of fact and such examination of law as we have deemed appropriate in order to enable us to render the opinions set forth herein. In conducting such investigation, we have relied, without independent verification, upon certificates of officers of the Company, public officials and other appropriate persons.

The opinions expressed below are limited to the Delaware General Corporation Law.

Based upon and subject to the foregoing, we are of the opinion that the Shares have been duly authorized and, when the Shares have been issued and sold in accordance with the terms of the applicable Plan, will be validly issued, fully paid and non-assessable.

We hereby consent to your filing this opinion as an exhibit to the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

---

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

---

## Exhibit 23.2

**Exhibit 23.2**

**Consent of Independent Registered Public Accounting Firm** 

We consent to the incorporation by reference in the Registration Statement (Form S-8) pertaining to the Acumen Pharmaceuticals, Inc. 2021 Equity Incentive Plan and the Acumen Pharmaceuticals, Inc. 2021 Employee Stock Purchase Plan of our report dated March 26, 2026, with respect to the financial statements of Acumen Pharmaceuticals, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2025, filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP

Philadelphia, Pennsylvania

March 26, 2026

<br>