Gad Soffer is COO at Atara Biotherapeutics, Inc. (ATRA). They have made 16 open-market trades across 1 company since 2015, most recently 2026-09-04.
CIK 0001604464
Unrated. We grade insiders only on stock they chose to buy on the open market. Grants, option exercises and vesting say nothing about timing, so they don't count — which is why someone can file often and still have no grade. It isn't a bad sign: unrated buys beat every graded tier below A.
1 open-market purchase totalling $1000K since 2026, against 15 sales. Too few scored purchases to measure a record yet.
| Ticker | Shares | Value |
|---|---|---|
| ATRA | 166,486 | $1.6M |
Shares reported on the most recent Form 4, priced at the 2026-09-04 close.
Counted per filing, not per execution lot — a purchase filled in several tranches is one decision.
| Ticker | Type | Traded | Filed | Price | Value | 7d Stock | 30d Stock | 90d Stock |
|---|---|---|---|---|---|---|---|---|
| ATRA | BUY | 2026-09-04 | 2026-09-04 | $9.60 | $1000K | -10.8% | -16.9% | — |
| ATRA | SELL | 2017-11-17 | 2017-11-17 | $15.00 | $105K | -1.4% | +0.3% | +221.2% |
| ATRA | SELL | 2017-08-15 | 2017-08-17 | $14.88 | $141K | +11.1% | +14.8% | +3.7% |
| ATRA | SELL | 2017-05-16 | 2017-05-17 | $15.19 | $86K | -11.1% | -14.4% | -4.4% |
| ATRA | SELL | 2017-05-15 | 2017-05-17 | $15.16 | $192K | -11.1% | -14.4% | -4.4% |
| ATRA | SELL | 2017-03-10 | 2017-03-13 | $20.00 | $50K | -5.8% | -21.5% | -41.3% |
| ATRA | SELL | 2017-02-14 | 2017-02-16 | $15.49 | $334K | +6.5% | +37.1% | -4.5% |
| ATRA | SELL | 2017-02-10 | 2017-02-13 | $15.44 | $188K | -8.3% | +25.2% | +2.0% |
| ATRA | SELL · 10b5-1 | 2016-11-17 | 2016-11-22 | $18.41 | $27K | +9.0% | -18.5% | -12.6% |
| ATRA | SELL | 2016-11-16 | 2016-11-16 | $19.27 | $138K | +9.9% | -14.2% | -15.8% |
| ATRA | SELL | 2016-11-14 | 2016-11-16 | $20.55 | $197K | +9.9% | -14.2% | -15.8% |
| ATRA | SELL | 2016-11-14 | 2016-11-16 | $20.00 | $334K | +9.9% | -14.2% | -15.8% |
| ATRA | SELL | 2016-08-16 | 2016-08-17 | $22.41 | $120K | -12.1% | -13.5% | -13.5% |
| ATRA | SELL | 2016-08-16 | 2016-08-17 | $22.44 | $118K | -12.1% | -13.5% | -13.5% |
| ATRA | SELL | 2016-05-17 | 2016-05-18 | $15.91 | $173K | +11.2% | +21.9% | +37.3% |
| ATRA | SELL | 2016-02-17 | 2016-02-18 | $17.13 | $65K | +12.0% | +11.6% | +3.8% |
| ATRA | SELL | 2016-02-17 | 2016-02-18 | $16.77 | $96K | +12.0% | +11.6% | +3.8% |
| ATRA | SELL · 10b5-1 | 2015-11-17 | 2015-11-18 | $31.22 | $237K | -24.2% | -6.6% | -39.5% |
| ATRA | SELL · 10b5-1 | 2015-08-17 | 2015-08-19 | $49.76 | $821K | -24.2% | -6.6% | -6.6% |
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.