ATRA

Atara Biotherapeutics, Inc.

Atara Biotherapeutics, Inc. (ATRA) has 9 SEC Form 4 filings (10 transaction rows) in the rolling window, disclosed by 4 distinct insiders. Most recent filing: Jul 25, 2026.

Insiders have net bought $1.5M over the trailing 6 months. The largest single insider purchase in this window was $4.7M by 10% Owner EcoR1 Capital, LLC on May 7, 2026.

  • Industry:Biotechnology
  • CEO:Anhco Nguyen
  • Employees:153
  • HQ:South San Francisco, CA, US
  • IPO:2014-10-16

Insider Buying

$4.7M

reported purchases (SEC code P)

Insider Selling

$3.2M

reported sales (SEC code S)

Unique Insiders

4

in the rolling window

Market Cap

$73.6M

latest known value

Source
Sale$22KMay 20SEC ↗
Nguyen AnhCoFirst filing
Sale$48KMay 20SEC ↗
Sale$3.2MMay 11SEC ↗
Purchase$4.7MMay 11SEC ↗

Related companies

Atara Biotherapeutics, Inc. is in the Healthcare sector.