WATER ISLAND CAPITAL LLC
CIK 1222765 · Holdings on Mar 31, 2026 · First reported May 15, 2026
Top ten holdings
Q1 2026- EA6.79%
- G4474Y2146.32%
- WBD5.92%
- 4364401015.64%
- TXNM5.26%
- PEN5.26%
- 16115Q3085.24%
- NSC5.13%
- MASI4.60%
- WED3.85%
Share classes counted separately54.01%
Portfolio value by quarter
What changed this quarter?
Within preview · weight change- G4474Y214Weight increased · +2.56 pp3.76% → 6.32%Shares +274.79K (+42.44%)
- EAWeight increased · +2.28 pp4.51% → 6.79%Shares +69.05K (+38.18%)
- WBDWeight increased · +1.91 pp4.01% → 5.92%Shares +477.39K (+41.89%)
Weight = security value ÷ total reported holdings value. Changes are in percentage points; price moves also affect weights, so they are not trade sizes.
Top 10 holdings 25
USD · B = billion · M = million; expand a row for exact values| # | Security | Value | Weight | Quantity | Weight / quantity change | Activity | |
|---|---|---|---|---|---|---|---|
| 01 | EAELECTRONIC ARTS INCEquity View history and evidence | $50.94M | 6.79% | 249.89K shares | 4.51% → 6.79%+2.28 pp +69.05K (+38.18%) | Added | ↗▾ |
| 02 | G4474Y214JANUS HENDERSON GROUP PLCEquity View history and evidence | $47.38M | 6.32% | 922.28K shares | 3.76% → 6.32%+2.56 pp +274.79K (+42.44%) | Added | ↗▾ |
| 03 | WBDWARNER BROS DISCOVERY INCEquity View history and evidence | $44.40M | 5.92% | 1.62M shares | 4.01% → 5.92%+1.91 pp +477.39K (+41.89%) | Added | ↗▾ |
| 04 | 436440101HOLOGIC INCEquity View history and evidence | $42.33M | 5.64% | 560.04K shares | 4.26% → 5.64%+1.38 pp +92.30K (+19.73%) | Added | ↗▾ |
| 05 | TXNMTXNM ENERGY INCEquity View history and evidence | $39.45M | 5.26% | 674.87K shares | 4.15% → 5.26%+1.11 pp +98.46K (+17.08%) | Added | ↗▾ |
| 06 | PENPENUMBRA INCEquity View history and evidence | $39.44M | 5.26% | 120.09K shares | Prior unavailable +120.09K | New | ↗▾ |
| 07 | 16115Q308CHART INDS INCEquity View history and evidence | $39.27M | 5.24% | 189.94K shares | 4.74% → 5.24%+0.50 pp +1.61K (+0.86%) | Added | ↗▾ |
| 08 | NSCNORFOLK SOUTHERN CORPEquity View history and evidence | $38.47M | 5.13% | 134.05K shares | 4.55% → 5.13%+0.58 pp +5.01K (+3.88%) | Added | ↗▾ |
| 09 | MASIMASIMO CORPEquity View history and evidence | $34.54M | 4.60% | 194.20K shares | Prior unavailable +194.20K | New | ↗▾ |
| 10 | WEDWEBSTER FINANCIAL CORPEquity View history and evidence | $28.87M | 3.85% | 415.82K shares | Prior unavailable +415.82K | New | ↗▾ |
Options overlay 12
$145.52M notionalPut and Call positions are separate. Notional is based on underlying securities, not option premium, market value or net exposure. Quantities are underlying shares.
| Security | Put / Call | Underlying shares | Notional | Quantity change | |
|---|---|---|---|---|---|
EAELECTRONIC ARTS INCEquity Put View history and evidence | Put | 149.80K | $30.54M | +149.80K | ▾ |
WBDWARNER BROS DISCOVERY INCEquity Put View history and evidence | Put | 1.05M | $28.82M | +954.60K (+1005.90%) | ▾ |
DAWNDAY ONE BIOPHARMACEUTICALS IEquity Put View history and evidence | Put | 839.70K | $18.00M | +839.70K | ▾ |
3 / 12 options · preview only
Exited positions 51
| Security | Type | Shares out | Value out | Previous filing | This filing |
|---|---|---|---|---|---|
| CYBR CYBERARK SOFTWARE LTD/ISRAEL | Non-derivative | -86,648 | -$38.65M | SEC filing ↗ | SEC filing ↗ |
| EXK EXACT SCIENCES CORP | Non-derivative | -350,009 | -$35.55M | SEC filing ↗ | SEC filing ↗ |
| CMA COMERICA INC | Non-derivative | -398,037 | -$34.60M | SEC filing ↗ | SEC filing ↗ |
3 / 51 preview exits. Up to 30 exit records are previewed. Exit means absent from the current filing; execution date, price and proceeds are unknown.
Every number has a source.
CIK 1222765 · Period 2026-03-31
Data loaded 2026-09-23 · First reported 2026-05-15
Amendments and versions
{
"amendments_merged": null,
"prior_versions": null,
"cover_table_value": 895644676
}Research all 98 reported holdings.
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