X0306 4 2016-12-19 0 0001339970 aTYR PHARMA INC LIFE 0001238362 MENDLEIN JOHN 3545 JOHN HOPKINS COURT, SUITE 250 SAN DIEGO CA 92121 1 1 0 0 CEO and Director Common Stock 2016-12-19 4 P 0 69000 2.198 A 324971 D Represents the weighted average price for the shares. The shares were purchased at prices ranging from $2.125 to $2.25 per share. The reporting person will provide to the Securities and Exchange Commission staff, the issuer, or any security holder of the issuer, upon request, full information regarding the number of shares purchased at each separate price. Includes 2,500 shares acquired under the Company's 2015 Employee Stock Purchase Plan ("ESPP") on May 15, 2016 and 2,500 shares acquired under the ESPP on November 15, 2016. /s/ Nancy Krueger, as Attorney-in-Fact 2016-12-21