Ken Griffin’s Atara Biotherapeutics ATRA Stock Holding History
Bought
Maintained
Sold
| Quarter | Market Value | Status | Shares |
Change in Stake | Trade Value | Portfolio Weight | Portfolio Position | |
|---|---|---|---|---|---|---|---|---|
|
2026
Q1 | – | Sell |
-15,577
| Closed | -$282K | – | 12944 |
|
|
2025
Q4 | $282K | Buy |
+15,577
| New | +$233K | ﹤0.01% | 10276 |
|
|
2025
Q3 | – | Sell |
-23,003
| Closed | -$178K | – | 12724 |
|
|
2025
Q2 | $178K | Buy |
+23,003
| New | +$168K | ﹤0.01% | 10791 |
|
|
2025
Q1 | – | Sell |
-267,353
| Closed | -$3.56M | – | 14437 |
|
|
2024
Q4 | $3.56M | Buy |
267,353
+6,873
| +3% | +$72.4K | ﹤0.01% | 4545 |
|
|
2024
Q3 | $2.12M | Hold |
260,480
| – | – | ﹤0.01% | 5430 |
|
|
2024
Q2 | $2.21M | Sell |
260,480
-3
| -0% | -$45 | ﹤0.01% | 5124 |
|
|
2024
Q1 | $4.52M | Buy |
260,483
+249,961
| +2,376% | +$4.44M | ﹤0.01% | 4096 |
|
|
2023
Q4 | $135K | Sell |
10,522
-56,324
| -84% | -$1.31M | ﹤0.01% | 10554 |
|
|
2023
Q3 | $2.47M | Buy |
66,846
+21,515
| +47% | +$958K | ﹤0.01% | 4836 |
|
|
2023
Q2 | $1.82M | Sell |
45,331
-44,738
| -50% | -$2.53M | ﹤0.01% | 5306 |
|
|
2023
Q1 | $6.53M | Buy |
90,069
+34,158
| +61% | +$3.31M | ﹤0.01% | 3383 |
|
|
2022
Q4 | $4.58M | Buy |
55,911
+54,648
| +4,327% | +$5.69M | ﹤0.01% | 3989 |
|
|
2022
Q3 | $119K | Buy |
1,263
+113
| +10% | +$12.7K | ﹤0.01% | 10942 |
|
|
2022
Q2 | $224K | Sell |
1,150
-4,240
| -79% | -$692K | ﹤0.01% | 10456 |
|
|
2022
Q1 | $1.25M | Buy |
5,390
+2,641
| +96% | +$841K | ﹤0.01% | 7192 |
|
|
2021
Q4 | $1.08M | Buy |
2,749
+1,447
| +111% | +$609K | ﹤0.01% | 7751 |
|
|
2021
Q3 | $583K | Buy |
1,302
+748
| +135% | +$268K | ﹤0.01% | 9494 |
|
|
2021
Q2 | $215K | Sell |
554
-8,018
| -94% | -$2.86M | ﹤0.01% | 12001 |
|
|
2021
Q1 | $3.08M | Sell |
8,572
-2,412
| -22% | -$1.07M | ﹤0.01% | 5381 |
|
|
2020
Q4 | $5.39M | Sell |
10,984
-7,421
| -40% | -$3.43M | ﹤0.01% | 3553 |
|
|
2020
Q3 | $5.96M | Buy |
18,405
+14,270
| +345% | +$4.86M | ﹤0.01% | 2906 |
|
|
2020
Q2 | $1.51M | Sell |
4,135
-10,761
| -72% | -$2.72M | ﹤0.01% | 5065 |
|
|
2020
Q1 | $3.17M | Buy |
14,896
+4,659
| +46% | +$1.48M | ﹤0.01% | 3370 |
|
|
2019
Q4 | $4.21M | Sell |
10,237
-15,497
| -60% | -$5.34M | ﹤0.01% | 3291 |
|
|
2019
Q3 | $9.08M | Buy |
25,734
+14,491
| +129% | +$5.41M | ﹤0.01% | 2330 |
|
|
2019
Q2 | $5.65M | Buy |
11,243
+10,630
| +1,734% | +$7.5M | ﹤0.01% | 2923 |
|
|
2019
Q1 | $609K | Buy |
+613
| New | +$570K | ﹤0.01% | 6453 |
|
|
2018
Q3 | – | Sell |
-227
| Closed | -$222K | – | 9183 |
|
|
2018
Q2 | $209K | Sell |
227
-592
| -72% | -$636K | ﹤0.01% | 7814 |
|
|
2018
Q1 | $799K | Buy |
+819
| New | +$746K | ﹤0.01% | 5143 |
|
|
2017
Q3 | – | Sell |
-1,458
| Closed | -$510K | – | 7505 |
|
|
2017
Q2 | $510K | Sell |
1,458
-1,085
| -43% | -$418K | ﹤0.01% | 5076 |
|
|
2017
Q1 | $1.31M | Buy |
+2,543
| New | +$1.05M | ﹤0.01% | 3608 |
|
|
2015
Q4 | – | Sell |
-355
| Closed | -$279K | – | 8704 |
|
|
2015
Q3 | $279K | Buy |
+355
| New | +$433K | ﹤0.01% | 5676 |
|
Other funds holding ATRA
RG
VCM
EC
Ken Griffin's ATRA Position: Q1 2026 in Review
Ken Griffin sold out of Atara Biotherapeutics (ATRA) in Q1 2026, closing a stake of 15,577 shares — an estimated $282K sold.
Ken Griffin first reported a position in ATRA in Q3 2015 and held it in 31 quarters. The position peaked at $9.08M in Q3 2019. 33 funds tracked by Wall St. Rank hold ATRA as of Q1 2026.
- Ken Griffin reported no remaining Atara Biotherapeutics position as of Q1 2026 after selling out during the quarter.
- Ken Griffin sold 15,577 Atara Biotherapeutics shares in Q1 2026, an estimated $282K.
- Ken Griffin first reported a position in Atara Biotherapeutics in Q3 2015 and held it in 31 quarters.
- Ken Griffin's Atara Biotherapeutics position peaked at $9.08M in Q3 2019.
- 33 funds tracked by Wall St. Rank held Atara Biotherapeutics as of Q1 2026.
Based on Citadel Advisors's 13F filing for Q1 2026, filed 15 May 2026.