# EDGAR Filing Document

**Accession Number:** 0001123494
**File Stem:** 0001104659-25-057943
**Filing Date:** 2025-6
**Character Count:** 6439
**Document Hash:** c4e8ec8363c3261f72ebe6f324ad0e1c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-057943.hdr.sgml**: 20250609

**ACCESSION NUMBER**: 0001104659-25-057943

**CONFORMED SUBMISSION TYPE**: 3

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20250602

**FILED AS OF DATE**: 20250609

**DATE AS OF CHANGE**: 20250609

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Duke John D
- **CENTRAL INDEX KEY:** 0002071593

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-33957
- **FILM NUMBER:** 251035776

**MAIL ADDRESS:**
- **STREET 1:** C/O HARVARD BIOSCIENCE, INC.
- **STREET 2:** 84 OCTOBER HILL ROAD
- **CITY:** HOLLISTON
- **STATE:** MA
- **ZIP:** 01746
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** HARVARD BIOSCIENCE INC
- **CENTRAL INDEX KEY:** 0001123494
- **STANDARD INDUSTRIAL CLASSIFICATION:** LABORATORY ANALYTICAL INSTRUMENTS [3826]
- **ORGANIZATION NAME:** 08 Industrial Applications and Services
- **EIN:** 043306140
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 84 OCTOBER HILL RD
- **CITY:** HOLLISTON
- **STATE:** MA
- **ZIP:** 01746
- **BUSINESS PHONE:** 5088938999

**MAIL ADDRESS:**
- **STREET 1:** 84 OCTOBER HILL ROAD
- **CITY:** HOLLISTON
- **STATE:** MA
- **ZIP:** 01746

## Ex-24

**Exhibit 24**

**POWER OF ATTORNEY**

KNOW ALL PERSONS BY THESE PRESENTS, that I, JOHN D. DUKE, hereby constitute and appoint Mark Mihanovic, Daniel L. Woodard, Matt Moreno, and each of them, my true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution for me and in my name, place and stead, to enroll me in EDGAR Next; act as an account administrator for my EDGAR account; appoint, remove and replace account administrators, account users, and delegated entities; maintain the security of my EDGAR account, including modification of access codes; maintain, modify and certify the accuracy of information on my EDGAR account dashboard; sign any Form ID (Uniform Application for Access Codes to File on EDGAR), reports on Form 3 (Initial Statement of Beneficial Ownership of Securities), Form 4 (Statement of Changes in Beneficial Ownership of Securities), Form 5 (Annual Statement of Beneficial Ownership of Securities) and Schedules 13D and 13G relating to transactions by me in shares of common stock or other securities of Harvard Bioscience, Inc. and all amendments thereto, and to file the same, with the Securities and Exchange Commission and the appropriate securities exchange. I hereby grant unto said attorneys-in-fact and agents, and each of them, or their substitutes, full power and authority to do and perform each and every act and thing requisite or necessary to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as I might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, and each of them, or their substitutes, may lawfully do or cause to be done by virtue hereof. The undersigned acknowledges that the foregoing attorneys-in-fact, in serving in such capacity at the request of the undersigned, are not assuming any of the undersigned's responsibilities to comply with Sections 13 and 16 of the Securities Exchange Act of 1934. This Power of Attorney shall be effective until such time as I deliver a written revocation thereof to the above-named attorneys-in-fact and agents.

---

| | | |
|:---|:---|:---|
| Dated: | 06/09/2025 | /s/ John D Duke |
| | | John D Duke |

---

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 3

### INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Duke John D<br><sub>(Last) (First) (Middle)</sub><br>C/O HARVARD BIOSCIENCE, INC.<br>84 OCTOBER HILL ROAD<br><sub>(Street)</sub><br>HOLLISTON, MA 01746<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>HARVARD BIOSCIENCE INC [ HBIO ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2025-06-02 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director   [ ] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities Beneficially Owned

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|  |  |  |  |
| --- | --- | --- | --- |
| 1. Title of Security | 2. Amount of Securities Beneficially Owned | 3. Ownership Form | 4. Nature of Indirect Beneficial Ownership |

---

## Table II - Derivative Securities Beneficially Owned

---

|  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 3. Title and Amount of Underlying Securities | 3. Title and Amount of Underlying Securities | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |

---

**Remarks:**
Exhibit 24 - Power of Attorney

**Signature:** /s/ John D Duke  
**Date:** 2025-06-09

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**