Ironwood Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US46333X1081

SecurityIRWD / Ironwood Pharmaceuticals, Inc.
InstitutionD. E. Shaw & Co., Inc.
ManagerDE Shaw
Latest Disclosed Ownership47,938 shares
Latest Disclosed Value $ 168,262
D. E. Shaw & Co., Inc. reports 59.18% decrease in ownership of IRWD / Ironwood Pharmaceuticals, Inc.

On May 15, 2026 - D. E. Shaw & Co., Inc. filed a 13F-HR form disclosing ownership of 47,938 shares of Ironwood Pharmaceuticals, Inc. (US:IRWD) valued at $168,262 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 117,446 shares of Ironwood Pharmaceuticals, Inc.. This represents a change in shares of -59.18% during the quarter. The current value of the position is $155,319 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)
2026-05-15 2026-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 47,938 -69,508 -59.18 168 -57.47 0.0001
2026-02-17 2025-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 117,446 -254,824 -68.45 396 -18.89 0.0002
2025-11-14 2025-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 372,270 -1,297,369 -77.70 488 -59.31 0.0003
2025-08-14 2025-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 1,669,639 1,559,915 1,421.67 1,197 643.48 0.0008
2025-05-15 2025-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 109,724 41,971 61.95 161 -46.33 0.0001
2025-02-14 2024-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 67,753 -176,928 -72.31 300 -70.24 0.0002
2024-11-14 2024-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 244,681 -140,268 -36.44 1,008 -59.82 0.0009
2024-08-14 2024-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 384,949 96,296 33.36 2,510 -0.20 0.0023
2024-05-15 2024-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 288,653 59,623 26.03 2,514 -4.05 0.0022
2024-02-14 2023-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 229,030 -207,233 -47.50 2,620 -37.63 0.0023
2023-11-14 2023-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 436,263 -482,735 -52.53 4,201 -57.04 0.0044
2023-08-14 2023-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 918,998 118,275 14.77 9,778 16.09 0.0100
2023-05-15 2023-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 800,723 173,337 27.63 8,424 8.36 0.0090
2023-02-14 2022-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 627,386 69,952 12.55 7,773 34.60 0.0086
2022-11-14 2022-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 557,434 -193,995 -25.82 5,775 -33.34 0.0069
2022-08-15 2022-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 751,429 -434,953 -36.66 8,664 -41.95 0.0102
2022-05-16 2022-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 1,186,382 302,288 34.19 14,925 44.79 0.0140
2022-02-14 2021-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 884,094 -441,333 -33.30 10,308 -40.45 0.0085
2021-11-15 2021-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 1,325,427 341,189 34.67 17,310 36.65 0.0156
2021-08-16 2021-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 984,238 -536,802 -35.29 12,667 -25.51 0.0109
2021-05-17 2021-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 1,521,040 -618,187 -28.90 17,005 -30.21 0.0164
2021-02-16 2020-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 2,139,227 290,922 15.74 24,366 46.55 0.0218
2020-11-16 2020-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 1,848,305 134,118 7.82 16,626 -6.01 0.0170
2020-08-14 2020-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 1,714,187 45,398 2.72 17,690 5.06 0.0211
2020-05-15 2020-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 1,668,789 203,163 13.86 16,838 -13.69 0.0263
2020-02-14 2019-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 1,465,626 797,330 119.31 19,508 240.04 0.0223
2019-11-14 2019-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 668,296 30,942 4.85 5,737 -17.71 0.0071
2019-08-14 2019-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 637,354 -350,178 -35.46 6,972 -47.82 0.0087
2019-05-15 2019-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 987,532 268,090 37.26 13,361 79.27 0.0173
2019-02-14 2018-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 719,442 479,462 199.79 7,453 68.24 0.0103
2018-11-14 2018-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 239,980 125,171 109.03 4,430 101.82 0.0053
2018-08-14 2018-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 114,809 -57,561 -33.39 2,195 -17.48 0.0029
2018-05-15 2018-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 172,370 -145,231 -45.73 2,660 -44.13 0.0036
2018-02-14 2017-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 317,601 25,744 8.82 4,761 3.43 0.0066
2017-11-14 2017-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 291,857 36,872 14.46 4,603 -4.38 0.0071
2017-08-14 2017-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 254,985 -269,609 -51.39 4,814 -46.21 0.0080
2017-05-15 2017-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 524,594 -105,400 -16.73 8,950 -7.09 0.0157
2017-02-14 2016-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 629,994 110,971 21.38 9,633 16.88 0.0164
2016-11-14 2016-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 519,023 223,568 75.67 8,242 113.36 0.0145
2016-08-15 2016-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 295,455 -27,547 -8.53 3,863 9.31 0.0071
2016-05-16 2016-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 323,002 32,671 11.25 3,534 5.02 0.0063
2016-02-16 2015-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 290,331 107,943 59.18 3,365 77.11 0.0050
2015-11-16 2015-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 182,388 -406,720 -69.04 1,900 -73.26 0.0028
2015-08-14 2015-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 589,108 -285,810 -32.67 7,105 -49.25 0.0106
2015-05-15 2015-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 874,918 154,687 21.48 13,999 26.87 0.0214
2015-02-17 2014-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 720,231 185,035 34.57 11,034 59.15 0.0142
2014-11-14 2014-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 535,196 411,549 332.84 6,933 265.66 0.0090
2014-08-14 2014-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 123,647 75,692 157.84 1,896 220.81 0.0026
2014-05-15 2014-03-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 47,955 -3,063 -6.00 591 -0.17 0.0008
2014-02-14 2013-12-31 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 51,018 -22,224 -30.34 592 -31.80 0.0008
2013-11-20 2013-09-30 13F/A-1 IRONWOOD PHARMACEUTICALS COM CL A 46333X108 73,242 -70,973 -49.21 868 -39.51 0.0014
2013-11-14 2013-09-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 73,242 868
2013-08-14 2013-06-30 13F IRONWOOD PHARMACEUTICALS COM CL A 46333X108 144,215 144,215 1,435 0.0027
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.