Westchester Capital Management, LLC holds a focused book of 297 stocks worth $2.1B as of Q1 2026 (disclosed May 15, 2026, a ~45-day 13F lag). This quarter they opened Webster Financial Corp and trimmed Proassurance Corp. Their largest long position is Electronic Arts Inc at 7% of the equity book. They also disclosed $140.6M in put options (a bearish bet), shown separately below and excluded from the equity book.
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curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/funds/1512805/holdings"
Use Arkolith to show Westchester Capital Management, LLC's latest holdings, largest changes, and filing provenance.
Top-heavy: focused book
Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.
91% mapped to company sectors
Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.
Estimated $ traded · quarter-end prices, no cost basis
Bars show each stock's share of the portfolio. Click a row for its position history.
| # | Security | Value | Shares | % Port | Last move | History |
|---|---|---|---|---|---|---|
| 1 | Electronic Arts Inc COM | $147.9M | 725.3K | 7.2% | ▲+22% Added · +131K sh | |
| 2 | Norfolk Southn Corp COM | $144.0M | 501.6K | 7.0% | ▲+29% Added · +114K sh | |
| 3 | Warner Bros Discovery Inc COM SER A | $143.7M | 5.23M | 7.0% | ▲+43% Added · +1.6M sh | |
| 4 | Webster Finl Corp COM | $127.3M | 1.83M | 6.2% | ▲New New position | |
| 5 | Chart Inds Inc COM | $102.6M | 496.1K | 5.0% | —Held | |
| 6 | Unifirst Corp Mass COM | $65.0M | 258.5K | 3.1% | ▲New New position | |
| 7 | Clearwater Analytics Hldgs I CL A | $61.9M | 2.62M | 3.0% | ▲New New position | |
| 8 | Coterra Energy Inc COM | $55.8M | 1.59M | 2.7% | ▲New New position | |
| 9 | Digitalbridge Group Inc CL A NEW | $45.3M | 2.94M | 2.2% | ▲New New position | |
| 10 | Sealed Air Corp New COM | $39.8M | 945.7K | 1.9% | ▲+11% Added · +92K sh | |
| 11 | Proassurance Corp COM | $36.0M | 1.46M | 1.7% | ▼−9.4% Reduced · −151K sh | |
| 12 | Hologic Inc COM | $34.4M | 455.3K | 1.7% | ▲+42% Added · +136K sh | |
| 13 | Penumbra Inc COM | $25.2M | 76.6K | 1.2% | ▲New New position | |
| 14 | Masimo Corp COM | $24.6M | 138.4K | 1.2% | ▲New New position | |
| 15 | Agriculture & Nat Sol Acq Co SHS CL A | $23.1M | 2.04M | 1.1% | ▲+4.1% Added · +80K sh | |
| 16 | Haymaker Acquisition Corp IV CLASS A | $22.2M | 1.94M | 1.1% | —Held | |
| 17 | Air Lease Corp CL A | $21.7M | 334.4K | 1.1% | —Held | |
| 18 | Qorvo Inc COM | $20.4M | 263.9K | 1.0% | ▲New New position | |
| 19 | Drugs Made In Amer Acqutn Co ORD SHS | $17.5M | 1.67M | 0.8% | —Held | |
| 20 | Onestream Inc CL A | $16.3M | 677.5K | 0.8% | ▲New New position | |
| 21 | Sizzle Acquisition Corp. II USD CL A ORD SHS | $16.0M | 1.56M | 0.8% | ▼−0.2% Reduced · −3K sh | |
| 22 | K&F Growth Acquisition Corp SHS CL A | $15.4M | 1.48M | 0.7% | ▼−22% Reduced · −409K sh | |
| 23 | Globa Terra Acquisition Cor CL A ORD SHS | $14.5M | 1.41M | 0.7% | —Held | |
| 24 | Titan Acquisition Corp CL A | $13.9M | 1.34M | 0.7% | —Held | |
| 25 | Gigcapital8 Corp ORD CL A | $13.3M | 1.33M | 0.6% | ▲+23% Added · +250K sh | |
| 26 | Oyster Enterprises II Acquis ORD SHS CL A | $13.2M | 1.30M | 0.6% | —Held | |
| 27 | Kochav Defense Acqui Co SHS CL A | $13.2M | 1.29M | 0.6% | —Held | |
| 28 | Soulpower Acquisition Corp USD CL A ORD SHS | $13.1M | 1.28M | 0.6% | —Held | |
| 29 | Siddhi Acquisition Corp CL A SHS | $13.0M | 1.25M | 0.6% | ▼−7.4% Reduced · −100K sh | |
| 30 | Pioneer Acquisition I Corp CL A ORD SHS | $12.8M | 1.26M | 0.6% | ▲+208% Added · +850K sh | |
| 31 | Jackson Acquisition Co II COM SHS CL A | $12.6M | 1.19M | 0.6% | —Held | |
| 32 | Aldel Finl II Inc CL A | $12.3M | 1.16M | 0.6% | —Held | |
| 33 | Janus Henderson Group PLC ORD SHS | $11.9M | 230.7K | 0.6% | ▲New New position | |
| 34 | Andretti Acquisition Corp II ORD SHS CL A | $11.8M | 1.11M | 0.6% | —Held | |
| 35 | New Providence Acquisition C USD CL A ORD SHS | $11.6M | 1.13M | 0.6% | ▼−12% Reduced · −150K sh | |
| 36 | Oxley Bridge Acq Ltd USD CL A ORD SHS | $11.3M | 1.12M | 0.5% | ▲+22% Added · +200K sh | |
| 37 | Voyager Acquisition Corp CL A | $10.3M | 961.9K | 0.5% | ▼−24% Reduced · −300K sh | |
| 38 | Artius II Acquisition Inc SHS CL A | $10.3M | 995.9K | 0.5% | —Held | |
| 39 | Cal Redwood Acquisition Corp COM CL A | $10.2M | 1.00M | 0.5% | ▲+54% Added · +350K sh | |
| 40 | Launch Two Acquisition Corp. ORD SHS CL A | $10.1M | 950.0K | 0.5% | —Held | |
| 41 | Apex Treas Corp ORD SHS CL A | $10.0M | 1.00M | 0.5% | ▲+100% Added · +500K sh | |
| 42 | Plum Acquisition Corp IV SHS CL A | $9.7M | 921.1K | 0.5% | ▼−25% Reduced · −304K sh | |
| 43 | Archimedes Tech Spac Partner ORD SHS | $9.4M | 907.1K | 0.5% | —Held | |
| 44 | Newbury STR II Acquisition C ORD SHS CL A | $9.4M | 898.1K | 0.5% | —Held | |
| 45 | Mountain Lake Acquisition Co SHS CL A | $9.3M | 887.7K | 0.5% | —Held | |
| 46 | GP-Act III Acquisition Corp CL A | $9.3M | 860.9K | 0.5% | ▼−37% Reduced · −500K sh | |
| 47 | Jena Acquisition Corp II USD CL A ORD SHS | $9.3M | 912.0K | 0.5% | —Held | |
| 48 | Apellis Pharmaceuticals Inc COM | $9.2M | 227.5K | 0.4% | ▲New New position | |
| 49 | GSR IV Acquisition Corp CL A SHS | $9.0M | 900.0K | 0.4% | ▲New New position | |
| 50 | Copley Acquisition Corp ORD SHS CL A | $8.9M | 860.6K | 0.4% | —Held |
Put / call positions from the 13F — totals include every disclosed option leg
| Type | Underlying | Notional value | Underlying shares |
|---|---|---|---|
| PUT · bearish | SS SPDR S&P 500 ETF TRUST-USSPY | $97.6M | 150K |
| PUT · bearish | KEURIG DR PEPPER INCKDP | $7.9M | 298K |
| PUT · bearish | APTIV PLCAPTV | $7.8M | 112K |
| PUT · bearish | BARRICK MINING CORPB | $6.3M | 155K |
| PUT · bearish | HONEYWELL INTERNATIONAL INCHON | $6.0M | 27K |
| PUT · bearish | CAESARS ENTERTAINMENT INCCZR | $5.8M | 218K |
| PUT · bearish | FEDEX CORPFDX | $5.6M | 16K |
| PUT · bearish | L3HARRIS TECHNOLOGIES INCLHX | $2.7M | 8K |
| PUT · bearish | KRAFT HEINZ CO/THEKHC | $983K | 44K |
| PUT · bearish | CLEARWATER ANALYTICS HDS-ACWAN | $50K | 2K |
13F filers disclose option positions at the market value of the underlying the contracts reference, not the premium paid. A put is a bearish bet (it gains if the stock falls); a call is bullish. “Underlying shares” is the share count the contracts control, not a share holding. These legs are excluded from the equity book, weighting, concentration and sector figures above.
As-of date vs the date the SEC received each filing
| Quarter | As of | Filed | Positions | Value | Form |
|---|---|---|---|---|---|
| Q1 2026 | Mar 31, 2026 | May 15, 2026 | 863 | $2.2B | 13F-HR |
| Q4 2025 | Dec 31, 2025 | Feb 13, 2026 | 778 | $2.4B | 13F-HR |
| Q3 2025 | Sep 30, 2025 | Nov 14, 2025 | 678 | $2.2B | 13F-HR |
| Q2 2025 | Jun 30, 2025 | Aug 14, 2025 | 511 | $1.9B | 13F-HR |
| Q1 2025 | Mar 31, 2025 | May 14, 2025 | 416 | $1.9B | 13F-HR |
| Q4 2024 | Dec 31, 2024 | Feb 14, 2025 | 393 | $1.8B | 13F-HR |
| Q3 2024 | Sep 30, 2024 | Nov 14, 2024 | 458 | $2.3B | 13F-HR |
| Q2 2024 | Jun 30, 2024 | Aug 14, 2024 | 558 | $2.7B | 13F-HR |
| Q1 2024 | Mar 31, 2024 | May 15, 2024 | 630 | $2.7B | 13F-HR |
| Q4 2023 | Dec 31, 2023 | Feb 15, 2024 | 691 | $2.9B | 13F-HR |
| Q3 2023 | Sep 30, 2023 | Nov 8, 2023 | 857 | $3.4B | 13F-HR |
| Q2 2023 | Jun 30, 2023 | Aug 14, 2023 | 901 | $3.2B | 13F-HR |
| Q1 2023 | Mar 31, 2023 | May 15, 2023 | 952 | $3.3B | 13F-HR |
| Q4 2022 | Dec 31, 2022 | Feb 14, 2023 | 1,195 | $3.6B | 13F-HR |
| Q3 2022 | Sep 30, 2022 | Nov 17, 2022 | 1,173 | $3.6B | 13F-HR/A |
| Q2 2022 | Jun 30, 2022 | Aug 15, 2022 | 1,106 | $3.6B | 13F-HR |
| Q1 2022 | Mar 31, 2022 | May 16, 2022 | 1,065 | $3.7B | 13F-HR |
| Q4 2021 | Dec 31, 2021 | Feb 14, 2022 | 1,041 | $3.5B | 13F-HR |
| Q3 2021 | Sep 30, 2021 | Nov 15, 2021 | 613 | $3.5B | 13F-HR |
| Q2 2021 | Jun 30, 2021 | Aug 13, 2021 | 553 | $4.3B | 13F-HR |
| Q1 2021 | Mar 31, 2021 | May 17, 2021 | 561 | $3.6B | 13F-HR |
| Q4 2020 | Dec 31, 2020 | Feb 12, 2021 | 386 | $3.1B | 13F-HR |
| Q3 2020 | Sep 30, 2020 | Nov 16, 2020 | 309 | $2.4B | 13F-HR |
Holdings from SEC EDGAR 13F-HR filings, updated quarterly ~45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. Price-derived performance is withheld until the price-source policy and freshness gate are green.