JANA Partners Management, LP holds a concentrated book of 11 stocks worth $1.7B as of Q1 2026 (disclosed Jun 30, 2026, a ~45-day 13F lag). This quarter they opened Everpure Inc-A and trimmed Mercury Systems Inc. Their largest long position is Mercury Systems Inc at 18% of the equity book.
The public view is the crawlable proof. The same sourced dataset is available through REST and MCP for agents, research scripts, and back-office tools.
This fund page is the Follow view. The Build view lets your agent pull holdings, quarter changes, overlap, and source filings through API or MCP.
curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/funds/1998597/holdings"
Use Arkolith to show JANA Partners Management, LP's latest holdings, largest changes, and filing provenance.
Top-heavy: concentrated book
Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.
85% 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 | Mercury Sys Inc COM | $299.5M | 4.11M | 18.0% | ▼−17% Reduced · −852K sh | |
| 2 | Cooper Cos Inc COM | $254.9M | 3.57M | 15.3% | ▲+1.3% Added · +46K sh | |
| 3 | Fiserv Inc COM | $247.5M | 4.44M | 14.8% | ▲+98% Added · +2.2M sh | |
| 4 | State STR SPDR S&P 500 ETF T TR UNIT | $223.5M | 343.7K | 13.4% | ▼−12% Reduced · −48K sh | |
| 5 | Lamb Weston Hldgs Inc COM | $211.7M | 5.01M | 12.7% | —Held | |
| 6 | Markel Group Inc COM | $144.1M | 75.3K | 8.6% | ▼−7.3% Reduced · −6K sh | |
| 7 | Alkami Technology Inc COM | $85.1M | 5.43M | 5.1% | ▲+11% Added · +537K sh | |
| 8 | Six Flags Entertainment Corp COM | $73.1M | 4.12M | 4.4% | —Held | |
| 9 | Everpure Inc CL A | $61.5M | 1.04M | 3.7% | ▲New New position | |
| 10 | Rapid7 Inc COM | $37.2M | 6.74M | 2.2% | —Held | |
| 11 | Enhabit Inc COM | $29.5M | 2.09M | 1.8% | —Held |
As-of date vs the date the SEC received each filing
| Quarter | As of | Filed | Positions | Value | Form |
|---|---|---|---|---|---|
| Q1 2026 | Mar 31, 2026 | Jun 30, 2026 | 11 | $1.7B | 13F-HR/A |
| Q4 2025 | Dec 31, 2025 | Feb 17, 2026 | 12 | $1.9B | 13F-HR |
| Q3 2025 | Sep 30, 2025 | Nov 14, 2025 | 12 | $2.1B | 13F-HR |
| Q2 2025 | Jun 30, 2025 | Aug 14, 2025 | 10 | $2.0B | 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.