13F Insight
DOSSIER · 13F Holders · Q1 2026Cheap mega-capRe-rated
IRWD

Ironwood Pharm

228 institutions still hold Ironwood Pharm as of Q1 2026. Tracked across SEC 13F-HR filings, with insider and 13D/G activity surfaced alongside.

CUSIP 46333x108·228 13F holders·last filed Mar 31, 2026
Market cap
—
▼ 4.7%
vs prior quarter
13F value held
$463M
50.0% inst. owned
of float
Holders
228
+71 QoQ
filers reporting
Activity
+39 / −7
+795 added · −666 reduced
this quarter
Concentration
11.40%
ARMISTICE CAPITAL, LLC #1
top holder share
AI Holders Summary · Q1 2026

228 institutions reported IRWD in Q1 2026. ARMISTICE CAPITAL, LLC leads at 11.4% of the visible book. +71 net new institutions vs prior quarter — accumulation reading.

Top holders

Sorted by position value. Source: SEC EDGAR 13F-HR filings.

#HolderValueShares% port.Quarter
01
ARMISTICE CAPITAL, LLC
CIK 0001601086
$53M15.0M0.94%Q1 202602
BlackRock, Inc.
CIK 0002012383
$47M13.4M0.00%Q1 202603
UBS Group AG
CIK 0001610520
$43M12.1M0.01%Q1 202604
Sarissa Capital Management LP
CIK 0001577524
$32M9.2M20.46%Q1 202605
BANK OF AMERICA CORP /DE/
CIK 0000070858
$30M8.7M0.00%Q1 202606
RENAISSANCE TECHNOLOGIES LLC
CIK 0001037389
$28M8.1M0.04%Q1 202607
AQR CAPITAL MANAGEMENT LLC
CIK 0001167557
$26M7.5M0.01%Q1 202608
STATE STREET CORP
CIK 0000093751
$26M7.5M0.00%Q1 202609
Vanguard Portfolio Management
CIK 0002100121· Index
$23M6.7M0.00%Q1 202610
VANGUARD CAPITAL MANAGEMENT LLC
CIK 0002100119· Index
$21M6.1M0.00%Q1 202611
TWO SIGMA INVESTMENTS, LP
CIK 0001179392
$21M5.8M0.02%Q1 202612
CHARLES SCHWAB INVESTMENT MANAGEMENT INC
CIK 0000884546· Index
$17M4.7M0.00%Q1 202613
GEODE CAPITAL MANAGEMENT, LLC
CIK 0001214717· Index
$16M4.5M0.00%Q1 202614
MARSHALL WACE, LLP
CIK 0001318757
$15M4.4M0.01%Q4 202515
JACOBS LEVY EQUITY MANAGEMENT, INC
CIK 0000884414
$13M3.6M0.05%Q1 202616
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP
CIK 0001164508
$12M3.4M0.01%Q1 202617
FEDERATED HERMES, INC.
CIK 0001056288
$12M3.3M0.02%Q1 202618
TWO SIGMA ADVISERS, LP
CIK 0001478735
$11M3.1M0.02%Q4 202519
GOLDMAN SACHS GROUP INC
CIK 0000886982
$9M2.7M0.00%Q1 202620
DIMENSIONAL FUND ADVISORS LP
CIK 0000354204· Quasi-passive
$7M2.1M0.00%Q1 2026
Page 1 of 12
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