X0306 4 2018-01-19 0 0001689813 Biohaven Pharmaceutical Holding Co Ltd. BHVN 0001329505 Bailey Gregory C/O BIOHAVEN PHARMACEUTICALS, INC. 234 CHURCH STREET NEW HAVEN CT 06510 1 0 0 0 Common Shares 2018-01-19 4 S 0 6812 29.20 D 2583289 D Common Shares 2018-01-19 4 S 0 17249 30.18 D 2566040 D Common Shares 2018-01-19 4 S 0 15939 31.08 D 2550101 D Common Shares 2018-01-22 4 S 0 9000 32.51 D 2541101 D The sales reported in the Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the record holder of the securities on August 19, 2017. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $28.75 - $29.71, 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 range set forth in footnote (2) to this Form 4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $29.75 - $30.74, 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 range set forth in footnote (3) to this Form 4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $30.75 - $31.25, 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 range set forth in footnote (4) to this Form 4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $32.50 - $32.60, 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 range set forth in footnote (5) to this Form 4. /s/ Darren K. DeStefano, attorney-in-fact 2018-01-23