Jane Street’s aTyr Pharma ATYR Stock Holding History

Jane Street’s Portfolio ATYR Stock Details ATYR Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q2	$8.95K	Buy	+15,000	New	+$9.8K	﹤0.01%	11315
2026 Q1	–	Sell	-44,700	Closed	-$35K	–	13258
2025 Q4	$35K	Buy	44,700 +32,500	+266%	+$26.7K	﹤0.01%	10606
2025 Q3	$8.8K	Sell	12,200 -6,000	-33%	-$27.2K	﹤0.01%	10585
2025 Q2	$92.3K	Sell	18,200 -62,300	-77%	-$245K	﹤0.01%	8986
2025 Q1	$243K	Buy	+80,500	New	+$294K	﹤0.01%	8156
2022 Q1	–	Sell	-13,700	Closed	-$102K	–	11150
2021 Q4	$102K	Sell	13,700 -38,100	-74%	-$318K	﹤0.01%	9247
2021 Q3	$470K	Buy	+51,800	New	+$310K	﹤0.01%	7392

Other funds holding ATYR

Federated Hermes Pittsburgh, Pennsylvania $69.6B AUM 42.52% 1-Year Est. Return

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

GCP

GSA Capital Partners London, United Kingdom $1.59B AUM 39.81% 1-Year Est. Return

AQR Capital Management Greenwich, Connecticut $287B AUM 42.33% 1-Year Est. Return

Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

KCM

Kalehua Capital Management Dallas, Texas $174M AUM

UBS Group Zurich, Switzerland $786B AUM 40.34% 1-Year Est. Return

Morgan Stanley New York $1.89T AUM 35.08% 1-Year Est. Return

Two Sigma Investments New York $138B AUM 41.87% 1-Year Est. Return

Jane Street's ATYR Position: Q2 2026 in Review

Jane Street increased its aTyr Pharma (ATYR) stake by 3,449% in Q2 2026, buying an estimated $1.09M and bringing the position to 1,721,297 shares worth $1.03M. The position accounts for ﹤0.01% of the portfolio, ranked #6491.

Jane Street first reported a position in ATYR in Q3 2018 and has held it in 14 quarters since. The position peaked at $1.24M in Q3 2021. 89 funds tracked by Wall St. Rank hold ATYR as of Q2 2026.

Jane Street held 1,721,297 shares of aTyr Pharma worth $1.03M as of Q2 2026.
Jane Street bought 1,672,795 aTyr Pharma shares in Q2 2026, an estimated $1.09M.
aTyr Pharma made up ﹤0.01% of Jane Street's portfolio in Q2 2026, its #6491 holding.
Jane Street first reported a position in aTyr Pharma in Q3 2018 and has held it in 14 quarters since.
Jane Street's aTyr Pharma position peaked at $1.24M in Q3 2021.
89 funds tracked by Wall St. Rank held aTyr Pharma as of Q2 2026.

Based on Jane Street's 13F filing for Q2 2026, filed 14 Aug 2026.