| CUSIP No. 046513 10 7 | 13G | Exhibit 99.1 |
AGREEMENT
Pursuant to Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree that only one statement containing the information required by Schedule 13G need be filed with respect to the ownership by each of the undersigned of Common Stock of Atara Biotherapeutics, Inc.
| Dated: February 17, 2015 | ||
| DAG VENTURES V-QP, L.P. | ||
| BY: | DAG VENTURES MANAGEMENT V, LLC | |
| ITS: | GENERAL PARTNER | |
| By: | /s/ R. Thomas Goodrich | |
| R. Thomas Goodrich | ||
| Managing Director | ||
| DAG VENTURES V, L.P. | ||
| BY: | DAG VENTURES MANAGEMENT V, LLC | |
| ITS: | GENERAL PARTNER | |
| By: | /s/ R. Thomas Goodrich | |
| R. Thomas Goodrich | ||
| Managing Director | ||
| DAG VENTURES MANAGEMENT V, LLC | ||
| By: | /s/ R. Thomas Goodrich | |
| R. Thomas Goodrich | ||
| Managing Director | ||
| /s/ R. Thomas Goodrich | ||
| R. Thomas Goodrich | ||
| /s/ John J. Cadeddu | ||
| John J. Cadeddu | ||