aTYR PHARMA INC — Director's Dealing 2020

May 28, 2020

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: aTYR PHARMA INC (LIFE)
CIK: 0001339970
Period of Report: 2020-05-16

Reporting Person: DENYES NANCY (General Counsel)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2020-05-16	Common Stock	M	892	—	Acquired	3057	Direct
2020-05-20	Common Stock	S	322	$3.62	Disposed	2735	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2020-05-26	Employee Stock Option (right to buy)	$4.06	A	30000	Acquired	2030-05-26	Common Stock (30000)	Direct
2020-05-16	Restricted Stock Unit	$	M	892	Disposed		Common Stock (892)	Direct

Footnotes

F1: Restricted stock units (RSU) convert into common stock on a one-for-one basis.

F2: Includes 178 shares acquired under the Company's 2015 Employee Stock Purchase Plan (ESPP) on May 15, 2020.

F3: Sale made by the Reporting Person in compliance with the provisions of Rule 10b5-1 to satisfy tax withholding obligations in connection with the partial vesting of RSUs granted on May 16, 2018.

F4: 50% of the shares subject to this option shall vest and become exercisable in 48 equal monthly installments beginning June 26, 2020, such that these shares will be fully exercisable on May 26, 2024; 25% of the shares subject to this option will vest on May 26, 2021 if and only if a clinical development milestone is achieved by September 30, 2020; and the remaining 25% of the shares will vest on May 26, 2021 if and only if an additional clinical development milestone is achieved by September 30, 2020.

F5: The RSU grant vests as to one-half (1/2) of the total number of units on each one year anniversary of the grant commencing on May 16, 2019.