Nguyen AnhCo 4

What Happened
Nguyen AnhCo, President, CEO and a director of Atara Biotherapeutics (ATRA), sold 5,241 shares on 2026-05-18 in an open-market/private sale for total proceeds of $47,845. The weighted average sale price was $9.13; individual sale prices ranged from $9.12 to $9.40. This was a sale (not a purchase) and appears to be a routine, tax-related transaction rather than an independent investment decision.

Key Details

• Transaction date: 2026-05-18. Filing date (Form 4): 2026-05-20 (timely filing).
• Transaction type: Sale (S); total shares sold: 5,241; weighted avg price: $9.13; price range: $9.12–$9.40.
• Reported proceeds: $47,845.
• Reason noted (Footnote F1): Shares were sold automatically to satisfy tax withholding arising from the vesting of previously granted restricted stock units (sale-to-cover).
• Footnote F2: Prices were aggregated as a weighted average; the filer can provide the exact share counts at each price on request.
• Shares owned after the transaction: not specified in the information provided here.

Context
Sale-to-cover transactions are a common, administrative outcome when restricted stock units vest and taxes are due; they do not necessarily signal the insider's view on the company’s prospects. This filing does not report option exercises or gifts; it documents an automatic sale for tax withholding.