aTyr Pharma, Inc.
US ˙ NasdaqCM ˙ US0021202025

SecurityATYR / aTyr Pharma, Inc.
InstitutionDimensional Fund Advisors Lp
Latest Disclosed Ownership91,871 shares
Latest Disclosed Value $ 71,479
Dimensional Fund Advisors Lp reports 5.77% decrease in ownership of ATYR / aTyr Pharma, Inc.

On May 7, 2026 - Dimensional Fund Advisors Lp filed a 13F-HR form disclosing ownership of 91,871 shares of aTyr Pharma, Inc. (US:ATYR) valued at $71,659 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 97,497 shares of aTyr Pharma, Inc.. This represents a change in shares of -5.77% during the quarter. The current value of the position is $43,179 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-07 2026-03-31 13F ATYR PHARMA COM NEW 002120202 91,871 -5,626 -5.77 71 -6.58 0.0000
2026-02-12 2025-12-31 13F ATYR PHARMA COM NEW 002120202 97,497 -117,049 -54.56 76 -50.97 0.0000
2025-11-12 2025-09-30 13F ATYR PHARMA COM NEW 002120202 214,546 0 0.00 155 -85.74 0.0000
2025-08-12 2025-06-30 13F ATYR PHARMA COM NEW 002120202 214,546 -13,548 -5.94 1,088 57.76 0.0003
2025-05-13 2025-03-31 13F ATYR PHARMA COM NEW 002120202 228,094 -15,275 -6.28 689 -21.70 0.0002
2025-02-13 2024-12-31 13F ATYR PHARMA COM NEW 002120202 243,369 97,845 67.24 881 243.75 0.0002
2024-11-07 2024-09-30 13F ATYR PHARMA COM NEW 002120202 145,524 0 0.00 256 12.78 0.0001
2024-08-09 2024-06-30 13F ATYR PHARMA COM NEW 002120202 145,524 -51,220 -26.03 227 -40.73 0.0001
2024-05-10 2024-03-31 13F ATYR PHARMA COM NEW 002120202 196,744 54,496 38.31 384 91.50 0.0001
2024-02-07 2023-12-31 13F ATYR PHARMA COM NEW 002120202 142,248 -94,201 -39.84 201 -46.38 0.0001
2023-11-09 2023-09-30 13F ATYR PHARMA COM NEW 002120202 236,449 -41,355 -14.89 374 -37.83 0.0001
2023-08-09 2023-06-30 13F ATYR PHARMA COM NEW 002120202 277,804 130,031 87.99 600 93.55 0.0002
2023-05-12 2023-03-31 13F ATYR PHARMA COM NEW 002120202 147,773 -49,919 -25.25 310 0.0001
2023-02-09 2022-12-31 13F ATYR PHARMA COM NEW 002120202 197,692 28,332 16.73 0 -100.00 0.0001
2022-11-10 2022-09-30 13F ATYR PHARMA COM NEW 002120202 169,360 21,764 14.75 508 21.53 0.0002
2022-08-12 2022-06-30 13F ATYR PHARMA COM NEW 002120202 147,596 -54,688 -27.04 418 -61.37 0.0001
2022-05-13 2022-03-31 13F ATYR PHARMA COM 002120202 202,284 -24,428 -10.77 1,082 -36.13 0.0003
2022-02-09 2021-12-31 13F ATYR PHARMA COM 002120202 226,712 2,433 1.08 1,694 -16.80 0.0005
2021-11-12 2021-09-30 13F ATYR PHARMA COM 002120202 224,279 3,351 1.52 2,036 88.87 0.0007
2021-08-12 2021-06-30 13F ATYR PHARMA COM 002120202 220,928 156,528 243.06 1,078 275.61 0.0003
2021-05-14 2021-03-31 13F ATYR PHARMA COM 002120202 64,400 45,270 236.64 287 287.84 0.0001
2021-03-08 2020-12-31 13F/A-2 ATYR PHARMA COM 002120202 19,130 0 0.00 74 19.35 0.0000
2021-02-11 2020-12-31 13F ATYR PHARMA COM 002120202 19,130 0 74 26.7249
2020-11-12 2020-09-30 13F ATYR PHARMA COM 002120202 19,130 2,500 15.03 62 -16.22 0.0000
2020-08-13 2020-06-30 13F ATYR PHARMA COM 002120202 16,630 -11,294 -40.45 74 -5.13 0.0000
2020-05-14 2020-03-31 13F ATYR PHARMA COM 002120202 27,924 27,924 78 0.0000
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.