Atara Biotherapeutics, Inc. (ATRA) Insider Ownership

Historic Insider Ownership Trends

As of April 17, 2026, the three largest insider holders of ATRA are Capital Fund I Lp Adiumentum (Director, 1.21Mn shares), Innovation Ltd Panacea (TenPercentOwner, 307.89K shares), Charlene A. Banard (Evp, Chief Technical Officer, 276.01K shares).

Top Direct Holders

Insider ownership data is derived from the last 60 months of Form 4 SEC filings.
Holder Position Shares (Direct) Shares (Indirect) Report Date
Capital Fund I Lp Adiumentum - 1,209,395 0 16 May, 2025
Innovation Ltd Panacea - 0 307,894 19 Mar, 2026
Charlene A. Banard Evp, Chief Technical Officer 276,010 0 18 May, 2023
Utpal Koppikar Chief Financial Officer 181,978 0 06 Mar, 2023
Kristin Yarema Chief Commercial Officer 171,415 0 03 Mar, 2022
Anhco Nguyen President And Ceo 143,078 0 11 Mar, 2026
Joe Newell Chief Operations Officer 113,097 0 18 Nov, 2021
Pascal Touchon President And Ceo 77,955 0 12 Jun, 2025
Yanina Grant-Huerta Chief Accounting Officer 52,050 0 11 Mar, 2026
Carol Giltner Gallagher - 33,012 0 12 Jun, 2025
Ronald C Jr Renaud - 31,500 0 27 Jun, 2022
Amar Murugan Evp, Chief Legal Officer 26,827 0 20 Aug, 2024
Jill Henrich Evp, Chief Regulatory Officer 18,679 0 05 Mar, 2025
Matthew K Fust - 18,188 0 12 Jun, 2025
Maria Grazia Roncarolo - 17,368 0 12 Jun, 2025
Ameet Mallik - 16,928 0 12 Jun, 2025

* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.

Recent Insider Transactions

Detailed insider trading activity based on Form 4 SEC filings.
Download Data
Transaction Date Insider Name Security Class Transaction Type Shares Traded Price Shares Remaining Ownership Code
17 Mar, 2026 Innovation Ltd Panacea Common Stock A 259,163 $0.00 307,899 I M
17 Mar, 2026 Innovation Ltd Panacea Common Stock D 5 $5.23 307,894 I F
17 Mar, 2026 Innovation Ltd Panacea Warrants D 259,163 $6.61 0 I M
09 Mar, 2026 Yanina Grant-Huerta Common Stock A 20,300 $0.00 52,050 D A
09 Mar, 2026 Anhco Nguyen Common Stock A 81,100 $0.00 143,078 D A
02 Mar, 2026 Anhco Nguyen Common Stock D 198 $5.08 64,776 D S
02 Mar, 2026 Yanina Grant-Huerta Common Stock D 24 $5.08 33,830 D S
02 Mar, 2026 Anhco Nguyen Common Stock D 58 $5.08 64,718 D S
02 Mar, 2026 Yanina Grant-Huerta Common Stock D 1,603 $5.08 32,227 D S
02 Mar, 2026 Yanina Grant-Huerta Common Stock D 377 $5.08 31,850 D S
02 Mar, 2026 Anhco Nguyen Common Stock D 1,298 $5.09 63,420 D S
02 Mar, 2026 Anhco Nguyen Common Stock D 1,442 $5.09 61,978 D S
02 Mar, 2026 Yanina Grant-Huerta Common Stock D 100 $5.08 31,750 D S
12 Jan, 2026 Innovation Ltd Panacea Common Stock D 80,554 $6.07 1,324,446 I S
28 Nov, 2025 Innovation Ltd Panacea Common Stock A 48,737 $0.00 48,737 I M
28 Nov, 2025 Innovation Ltd Panacea Common Stock D 1 $14.03 48,736 I F
28 Nov, 2025 Innovation Ltd Panacea Warrants D 48,737 $6.61 259,163 I M
17 Nov, 2025 Anhco Nguyen Common Stock D 2,859 $13.19 65,030 D S
17 Nov, 2025 Yanina Grant-Huerta Common Stock D 1,645 $13.19 33,613 D S
17 Nov, 2025 Yanina Grant-Huerta Common Stock D 85 $13.19 33,528 D S