Company: ATRA
Filing Date: 2025-03-07
Form Type: 10-K
Source: 0000950170-25-035507
Chunk: 234

Company: Atara Biotherapeutics, Inc.
Filing Date: 2025-03-07
Form: 10-K
Item: Item 1B
Chunk 234
---
        $
        39.09

      The weighted average grant date fair value of RSUs granted during the years ended December 31, 2024 and 2023 was $13.76 and $89.25, respectively. The estimated fair value of RSUs that vested in the years ended December 31, 2024 and 2023 was $24.9 million and $32.8 million, respectively. As of December 31, 2024, there was $14.0 million of unrecognized stock-based compensation expense related to RSUs that is expected to be recognized over a weighted average period of 1.4 years. The aggregate intrinsic value of the RSUs outstanding as of December 31, 2024 was $5.5 million. Under our RSU settlement procedures, for some of the RSUs granted to our employees, we withhold shares at settlement to cover the estimated payroll withholding tax obligations. During 2024, we settled 315,109 shares underlying RSUs, of which 987 shares underlying RSUs were net settled by withholding 366 shares. The value of the shares underlying RSUs withheld was not material, based on the closing price of our common stock on the settlement date. During 2023, we settled 147,520 shares underlying RSUs, of which 2,050 shares underlying RSUs were net settled by withholding 728 shares. The value of the shares underlying RSUs withheld was $0.1 million, based on the closing price of our common stock on the settlement date. The value of RSUs withheld in each period was remitted to the appropriate taxing authorities and has been reflected as a financing activity in our consolidated statements of cash flows. Stock Options The following is a summary of stock option activity under our 2014 EIP, 2024 EIP and Inducement Plan:

        Shares

        Weighted Average Exercise Price

        Weighted AverageRemainingContractualTerm (Years)

        AggregateIntrinsic Value (in thousands)

        Balance as of December 31, 2023

        428,786

        $
        290.75

        6.5

        $
        —

        Granted

        16,500

        11.00

        Exercised

        —

        —

        Forfeited or expired

        (211,143
        )

        349.66

        Balance as of December 31, 2024

        234,143

        $
        217.