Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
GREEN DAVID
   2. Issuer Name and Ticker or Trading Symbol
HARVARD BIOSCIENCE INC [HBIO] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President
(Last)
(First)
(Middle)
84 OCTOBER HILL ROAD		 3. Date of Earliest Transaction (Month/Day/Year)
03/31/2011
(Street)

HOLLISTON, MA 01746		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 03/29/2011   S   40,800 (1) D $ 6.0145 (2) 1,522,602 (3) D  
Common Stock 03/30/2011   S   37,300 (1) D $ 6.0796 (4) 1,485,302 (5) D  

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
GREEN DAVID
84 OCTOBER HILL ROAD
HOLLISTON, MA 01746		   X     President  

Signatures

 Thomas McNaughton   03/31/2011
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) Represents shares sold by Mr. Green pursuant to a Sales Plan under Rule 10b5-1 adopted by the reporting person in September 2009.
(2) Reflects the weighted average price of the shares sold in the reported transaction. These shares were sold in multiple transactions at prices ranging from $5.95 to $6.17, inclusive. The reporting person undertakes to provide to Harvard Bioscience, Inc., any security holder of Harvard Bioscience, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.
(3) Includes (a) a deferred stock award of 100,200 restricted stock units which vest in equal installments on January 1, 2012; January 1, 2013 and January 1, 2014; and (b) 1,422,402 shares of common stock held by Mr. Green.
(4) Reflects the weighted average price of the shares sold in the reported transaction. These shares were sold in multiple transactions at prices ranging from $5.95 to $6.22, inclusive. The reporting person undertakes to provide to Harvard Bioscience, Inc., any security holder of Harvard Bioscience, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.
(5) Includes (a) a deferred stock award of 100,200 restricted stock units which vest in equal installments on January 1, 2012; January 1, 2013 and January 1, 2014; and (b) 1,385,102 shares of common stock held by Mr. Green.

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