Atara Biotherapeutics, Inc. — Director's Dealing 2015

Nov 19, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Atara Biotherapeutics, Inc. (ATRA)
CIK: 0001604464
Period of Report: 2015-11-16

Reporting Person: MCGRATH JOHN (Chief Financial Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2015-11-16	Common Stock	M	2805	$0.00	Acquired	34659	Direct
2015-11-16	Common Stock	M	7697	$0.00	Acquired	42356	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2015-11-16	Restricted Stock Units	$	M	2805	Disposed		Common Stock (2805)	Indirect
2015-11-16	Restricted Stock Units	$	M	7697	Disposed		Common Stock (7697)	Indirect

Footnotes

F1: Shares issued upon settlement of vested restricted stock units ("RSUs").

F2: Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock or a cash settlement.

F3: The RSUs were granted with both (a) a liquidity event-based vesting condition and (b) a service-based vesting condition, both of which conditions must be satisfied in order for the RSUs to vest. The liquidity event-based condition was satisfied upon the closing of the Issuer's initial public offering (the "IPO"). The shares that vested on the closing date of the IPO, and the shares that vested thereafter through May 15, 2015, were settled on May 15, 2015. The service-based vesting condition provides that 25% of the total number of shares on March 13, 2014 and 1/48th of the total number of shares monthly thereafter, subject to the holder's continuous service through each such date.

F4: The earlier of (i) March 13, 2020 or (ii) the recepient's termination date.

F5: The shares are held by the David B. Horowitz and John McGrath Jr. Revocable Living Trust dated 6/3/11, of which the Reporting Person is trustee.

F6: The RSUs were granted with both (a) a liquidity event-based vesting condition and (b) a service-based vesting condition, both of which conditions must be satisfied in order for the RSUs to vest. The liquidity event-based condition was satisfied upon the closing of the Issuer's initial public offering (the "IPO"). The shares that vested on the closing date of the IPO, and the shares that vested thereafter through May 15, 2015, were settled on May 15, 2015. The service-based vesting condition provides that 25% of the total number of shares on January 6, 2015 and 1/48th of the total number of shares monthly thereafter, subject to the holder's continuous service through each such date.

F7: The earlier of (i) December 12, 2020 or (ii) the recipient's termination date.