Syndax Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US87164F1057

SecuritySNDX / Syndax Pharmaceuticals, Inc.
InstitutionFox Run Management, L.l.c.
Latest Disclosed Ownership21,993 shares
Latest Disclosed Value $ 494,403
Fox Run Management, L.l.c. reports 45.43% decrease in ownership of SNDX / Syndax Pharmaceuticals, Inc.

On May 12, 2026 - Fox Run Management, L.l.c. filed a 13F-HR form disclosing ownership of 21,993 shares of Syndax Pharmaceuticals, Inc. (US:SNDX) valued at $513,756 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 40,302 shares of Syndax Pharmaceuticals, Inc.. This represents a change in shares of -45.43% during the quarter. The current value of the position is $403,352 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)
2026-05-12 2026-03-31 13F SYNDAX PHARMACEUTICALS COM 87164F105 21,993 -18,309 -45.43 494 -41.61 0.0865
2026-02-11 2025-12-31 13F SYNDAX PHARMACEUTICALS COM 87164F105 40,302 4,646 13.03 847 54.38 0.1307
2025-11-12 2025-09-30 13F SYNDAX PHARMACEUTICALS COM 87164F105 35,656 17,293 94.17 549 220.47 0.0855
2025-08-06 2025-06-30 13F SYNDAX PHARMACEUTICALS COM 87164F105 18,363 18,363 172 0.0287
2025-05-13 2025-03-31 13F SYNDAX PHARMACEUTICALS COM 87164F105 0 -16,355 -100.00 0 -100.00
2025-02-11 2024-12-31 13F SYNDAX PHARMACEUTICALS COM 87164F105 16,355 -13,601 -45.40 216 -62.50 0.0393
2024-11-12 2024-09-30 13F SYNDAX PHARMACEUTICALS COM 87164F105 29,956 -25,879 -46.35 577 -49.74 0.1283
2024-08-13 2024-06-30 13F SYNDAX PHARMACEUTICALS COM 87164F105 55,835 55,835 1,146 0.2157
2024-02-13 2023-12-31 13F SYNDAX PHARMACEUTICALS COM 87164F105 0 -15,320 -100.00 0 -100.00
2023-11-07 2023-09-30 13F SYNDAX PHARMACEUTICALS COM 87164F105 15,320 15,320 222 0.0658
2023-08-11 2023-06-30 13F SYNDAX PHARMACEUTICALS COM 87164F105 0 -13,214 -100.00 0 -100.00
2023-05-12 2023-03-31 13F SYNDAX PHARMACEUTICALS COM 87164F105 13,214 13,214 279 0.0909
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.