X0306 4 2018-03-08 0 0001123494 HARVARD BIOSCIENCE INC HBIO 0001585223 Duchemin Jeffrey HARVARD BIOSCIENCE, INC. 84 OCTOBER HILL ROAD HOLLISTON MA 01746 1 1 0 0 Chief Executive Officer Common Stock 2018-03-08 4 S 0 79222 4.52 D 649654 D Common Stock 2018-03-09 4 S 0 7800 4.60 D 641854 D The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $4.50 to $4.68, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 footnote (1) to this Form 4. Includes (a) a deferred stock award of 268,206 restricted stock units which shall vest in three equal installments on January 1, 2019, 2020 and 2021; (b) a deferred stock award of 145,833 restricted stock units which shall vest in two equal installments on January 1, 2019 and 2020; (c) a deferred stock award of 17,225 restricted stock units which shall vest in full on January 1, 2019; (d) a deferred stock award of 71,748 restricted stock units with performance based vesting conditions, which shall vest on August 3, 2018 contingent upon achievement of a performance condition tied to relative total shareholder return; and (e) 146,642 shares of common stock held by the Reporting Person. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $4.60 to $4.65, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 footnote (1) to this Form 4. Includes (a) a deferred stock award of 268,206 restricted stock units which shall vest in three equal installments on January 1, 2019, 2020 and 2021; (b) a deferred stock award of 145,833 restricted stock units which shall vest in two equal installments on January 1, 2019 and 2020; (c) a deferred stock award of 17,225 restricted stock units which shall vest in full on January 1, 2019; (d) a deferred stock award of 71,748 restricted stock units with performance based vesting conditions, which shall vest on August 3, 2018 contingent upon achievement of a performance condition tied to relative total shareholder return; and (e) 138,842 shares of common stock held by the Reporting Person. This form has been signed under power of attorney. /s/ Chad Porter, by power of attorney 2018-03-12