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 Q1	$353K	Buy	452,900 +162,400	+56%	+$137K	﹤0.01%	8851
2025 Q4	$227K	Sell	290,500 -393,300	-58%	-$323K	﹤0.01%	9458
2025 Q3	$493K	Buy	683,800 +582,600	+576%	+$2.64M	﹤0.01%	7890
2025 Q2	$513K	Buy	+101,200	New	+$398K	﹤0.01%	6874
2021 Q4	–	Sell	-171,200	Closed	-$1.55M	–	10926
2021 Q3	$1.55M	Buy	+171,200	New	+$1.02M	﹤0.01%	5002

Other funds holding ATYR

Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

Federated Hermes Pittsburgh, Pennsylvania $61.5B AUM 30.7% 1-Year Est. Return

BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return

UBS Group Zurich, Switzerland $666B AUM 30.12% 1-Year Est. Return

VCM

Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM

Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return

State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return

GCP

GSA Capital Partners London, United Kingdom $1.61B AUM 28.28% 1-Year Est. Return

Millennium Management New York $240B AUM 35.51% 1-Year Est. Return

Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return

Jane Street's ATYR Position: Q1 2026 in Review

Jane Street reduced its aTyr Pharma (ATYR) stake by 74% in Q1 2026, selling an estimated $118K and leaving 48,502 shares worth $37.8K. The position accounts for ﹤0.01% of the portfolio, ranked #11058.

Jane Street first reported a position in ATYR in Q3 2018 and has held it in 13 quarters since. The position peaked at $1.24M in Q3 2021. 111 funds tracked by Wall St. Rank hold ATYR as of Q1 2026.

Jane Street held 48,502 shares of aTyr Pharma worth $37.8K as of Q1 2026.
Jane Street sold 139,647 aTyr Pharma shares in Q1 2026, an estimated $118K.
aTyr Pharma made up ﹤0.01% of Jane Street's portfolio in Q1 2026, its #11058 holding.
Jane Street first reported a position in aTyr Pharma in Q3 2018 and has held it in 13 quarters since.
Jane Street's aTyr Pharma position peaked at $1.24M in Q3 2021.
111 funds tracked by Wall St. Rank held aTyr Pharma as of Q1 2026.

Based on Jane Street's 13F filing for Q1 2026, filed 12 May 2026.