1.	Description of Business

Atara Biotherapeutics, Inc. (“Atara”, “we”, “our” or “the Company”) was incorporated in August 2012 in Delaware. Atara is a clinical-stage biopharmaceutical company focused on developing meaningful therapies for patients with severe and life-threatening diseases that have been underserved by scientific innovation. We have two groups of product candidates: (a) allogeneic or third-party derived antigen-specific T-cells, and (b) molecularly targeted biologics.

Our T-cell programs were acquired through licensing arrangements with Memorial Sloan Kettering Cancer Center (“MSK”). Our molecularly targeted biologics programs were acquired through licensing arrangements with Amgen Inc. (“Amgen”). In December 2015, we announced that we were suspending our PINTA 745 program, which was originally licensed from Amgen. See Note 6 for further information.

In October 2014, we completed our initial public offering (“IPO”) of 5,750,000 shares of common stock at an offering price to the public of $11.00 per share. We received net proceeds of $56.5 million, after deducting underwriting discounts and commissions and offering expenses. In connection with the IPO, our outstanding shares of convertible preferred stock were automatically converted into 12,298,515 shares of common stock, resulting in the reclassification of $74.6 million from mezzanine equity to additional paid-in capital.

In February 2015, we completed a follow-on offering of 4,147,358 shares of common stock at an offering price to the public of $18.00 per share. We received net proceeds of $69.5 million, after deducting underwriting discounts and commissions and offering expenses.

In July 2015, we completed a follow-on offering of 3,980,768 shares of common stock at an offering price to the public of $52.00 per share. We received net proceeds of $193.9 million, after deducting underwriting discounts and commissions and offering expenses.