WATER ISLAND CAPITAL LLC

Fundamental concentrated ★Signal CIK 1222765
Long book
$710.8M
Q1 2026
Positions
77
Top-10 weight
57%
concentration
Last quarter
+4.3%
SPY +14.8%
Turnover
77%
of book per quarter

Strategy in plain words

auto-generated from filings

WATER ISLAND CAPITAL LLC is a concentrated fundamental stock-picker, running a $710.8M US long book across 77 positions.

The portfolio is concentrated: the top 10 names carry 57% of the portfolio. Turnover is high — positions rotate quickly, so individual names matter less than the process. Current anchor positions: ELECTRONIC ARTS INC, Janus Hendersongroup Pl, WARNER BROS DISCOVERY INC, HOLOGIC INC, TXNM ENERGY INC.

Over the last 9 quarters its long book ran on average 4pp per quarter behind the S&P 500, beating the index in 3 of 9 quarters. We rate its filings as signal-bearing: position changes reflect genuine views.

Implied long-book return vs S&P 500

methodology: positions priced quarterly, no shorts/options
Fund long book S&P 500
Q1 2024
-11.7%
Q2 2024
-1.8%
Q3 2024
+9.2%
Q4 2024
+5.6%
Q1 2025
+1.6%
Q2 2025
+3.1%
Q3 2025
-3.0%
Q4 2025
-2.5%
Q1 2026
+4.3%

Sector allocation

Other
39%
Industrials
15%
Financials
11%
Technology
11%
Communications
8%
Healthcare
7%
Utilities
7%
Services media
2%

Long book by quarter

$858.9M
Q1 2024
$899.0M
Q2 2024
$914.1M
Q3 2024
$767.5M
Q4 2024
$531.4M
Q1 2025
$523.0M
Q2 2025
$647.1M
Q3 2025
$765.8M
Q4 2025
$710.8M
Q1 2026

What does WATER ISLAND own?

Q1 2026 13F
CompanySectorSharesValue% of bookChange
EA ELECTRONIC ARTS INCTechnology249.9K$50.9M7.2%+38.2%
WBD WARNER BROS DISCOVERY INCCommunications1.6M$44.4M6.2%+41.9%
HO1 HOLOGIC INC560.0K$42.3M6.0%+19.7%
TXNM TXNM ENERGY INCUtilities674.9K$39.5M5.6%+17.1%
PEN PENUMBRA INCHealthcare120.1K$39.4M5.5%New
GTLS CHART INDUSTRIES INCIndustrials189.9K$39.3M5.5%+0.9%
NSC NORFOLK SOUTHERN CORPIndustrials134.1K$38.5M5.4%+3.9%
MASI* MASIMO CORP194.2K$34.5M4.9%New
WBS WEBSTER FINANCIAL CORPFinancials415.8K$28.9M4.1%New
T86 TRI POINTE HOMES INC536.4K$25.1M3.5%New
GLDD GREAT LAKES DREDGE & DOCK CO1.3M$21.5M3.0%New
ACLXGBX ARCELLX INC183.4K$21.1M3.0%New
DAWNGBX DAY ONE BIOPHARMACEUTICALS I944.2K$20.2M2.8%New
DBRG DIGITALBRIDGE GROUP INCFinancials1.3M$20.0M2.8%+39.8%
STEL STELLAR BANCORP INCFinancials431.2K$15.8M2.2%New
EHABUSD ENHABIT INC984.6K$13.9M2.0%New
SLAB SILICON LABORATORIES INCTechnology58.4K$12.2M1.7%New
KVUE KENVUE INCOther700.6K$12.1M1.7%+1.5%
430 TERNS PHARMACEUTICALS INC188.5K$9.9M1.4%New
ZIM ZIM INTEGRATED SHIPPING SERVIndustrials331.8K$8.7M1.2%New
UNF UNIFIRST CORP/MAServices media25.7K$6.5M0.9%New
AXTA AXALTA COATING SYSTEMS LTDOther206.9K$5.7M0.8%+0.6%
APLSUSD APELLIS PHARMACEUTICALS INC120.5K$4.8M0.7%New
AL AIR LEASE CORP73.1K$4.7M0.7%-75.5%
AES AES CORPUtilities185.8K$2.6M0.4%New
SDA SEALED AIR CORPServices media56.1K$2.4M0.3%-90.0%
AAUC ALLIED GOLD CORP72.8K$2.3M0.3%New
K4F ONESTREAM INC91.1K$2.2M0.3%New
BHF BRIGHTHOUSE FINANCIAL INCFinancials33.5K$2.0M0.3%+16.1%
NATL NCR ATLEOS CORPTechnology38.9K$1.7M0.2%New
SEM SELECT MEDICAL HOLDINGS CORPHealthcare103.5K$1.7M0.2%New
8TG THERMON GROUP HOLDINGS INC33.0K$1.7M0.2%New
SNCY SUN COUNTRY AIRLINES HOLDING98.9K$1.6M0.2%New
VICI Vici properties incReal estate20.2K$1.6M0.2%-86.6%
628 SEMRUSH HOLDINGS INC-A133.9K$1.6M0.2%-78.7%
AM6 AMICUS THERAPEUTICS INC104.1K$1.5M0.2%-85.3%
BA BOEING CO/THEIndustrials7.2K$1.4M0.2%New
STKL SUNOPTA INC196.5K$1.3M0.2%New
PRA PROASSURANCE CORPFinancials51.1K$1.3M0.2%+8.7%
UTE0 CANTALOUPE INC107.9K$1.2M0.2%-18.2%
CCO CLEAR CHANNEL OUTDOOR HOLDINServices media478.5K$1.1M0.2%New
IHS IHS HOLDING LTDCommunications137.6K$1.1M0.2%New
TALK TALKSPACE INCHealthcare216.2K$1.1M0.2%New
DKS DICK'S SPORTING GOODS INCConsumer discretionary5.3K$1.1M0.1%+386.2%
CTRA COTERRA ENERGY INC27.3K$959K0.1%New
SKYT SKYWATER TECHNOLOGY INCTechnology34.5K$947K0.1%New
NWE NORTHWESTERN ENERGY GROUP INUtilities13.8K$912K0.1%-3.3%
AMRX AMNEAL PHARMACEUTICALS INCHealthcare68.4K$850K0.1%New
CZR CAESARS ENTERTAINMENT INCServices media29.5K$780K0.1%New
7WH UDEMY INC139.3K$644K0.1%+2.5%

13F filing history

PeriodFormFiledEntriesReported valueFlagsSource
Q1 202613F-HRMay 15, 202698$895.6M canonicalSEC ↗
Q4 202513F-HRFeb 17, 202691$927.6M canonicalSEC ↗
Q3 202513F-HRNov 14, 202584$793.3M canonicalSEC ↗
Q2 202513F-HRAug 14, 202576$702.0M canonicalSEC ↗
Q1 202513F-HRMay 15, 202584$764.1M canonicalSEC ↗
Q4 202413F-HRFeb 13, 202578$925.7M canonicalSEC ↗
Q3 202413F-HRNov 14, 202479$992.7M canonicalSEC ↗
Q2 202413F-HR/ARESTATEMENTNov 14, 202475$986.6M canonicalSEC ↗
Q2 202413F-HRAug 15, 202471$943K SEC ↗
Q1 202413F-HR/ARESTATEMENTNov 14, 202461$961.8M canonicalSEC ↗
Q1 202413F-HRMay 15, 202459$884K SEC ↗