JANA Partners Management, LP — 13F Holdings & Portfolio
CIK 1998597 · latest 13F-HR filed 2026-08-14
JANA Partners Management, LP manages $1.90B in 13F-reported U.S. long-equity assets across 10 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are MRCY (25.46%), COO (13.50%), SPY (13.46%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 1 new position and exited 1; 6 existing positions rose in reported value and 1 fell.
AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.
Long-equity book
Distinct positions
Filed 2026-08-14
vs 2026-03-31
Portfolio charts
Latest quarter's book, what changed, and how the portfolio has evolved across filings.
Portfolio map
Q2 26Box size = position value; colour = change in share count vs the prior quarter (green added, red trimmed, blue new). Rows split across managers or share classes are combined. Click a box for the stock.
Sector mix
% of 13F valueSectors from each company's SIC code; funds and ETFs grouped separately.
Biggest buys and sells
Q1 26 → Q2 26Estimated from the change in shares held × the quarter-end price, so price moves alone don't count as buying. New and exited positions are included.
13F assets and positions
4 quartersTotal reported 13F value (bars) and number of positions (line) each quarter. Value changes include market moves.
Top positions over time
reported valueThe eight largest current positions, valued at each quarter end.
Concentration
top 10 = 100%Cumulative share of the portfolio held in the largest N positions.
24TH FLOOR
NEW YORK, NY 10106
| Name | Title / Status | Ownership | Type |
|---|---|---|---|
| CANNAE HOLDINGS, INC. Control | MEMBER | 75% or more | Domestic Entity |
| CANNAE HOLDINGS, LLC Control | SPECIAL LIMITED PARTNER | 25–50% | Domestic Entity |
| CANNAE HOLDINGS, LLC Control | SPECIAL MEMBER | 50–75% | Domestic Entity |
| CASWELL, RYAN, RICHARD Control | DIRECTOR | General partner | Individual |
| FANJIANG, JENNIFER Control | PARTNER, CHIEF LEGAL OFFICER & CHIEF COMPLIANCE OFFICER | LIMITED PARTNER | 5–10% | Individual |
| GALLIGAN, KEVIN, GARVEY Control | PARTNER | LIMITED PARTNER | 5–10% | Individual |
| GRAVELLE, MICHAEL, LOUIS Control | DIRECTOR | General partner | Individual |
| JANA PARTNERS MANAGEMENT GP, LLC Control | GENERAL PARTNER | Less than 5% | Domestic Entity |
| OSTFELD, SCOTT, DAVID Control | DIRECTOR | General partner | Individual |
| OSTFELD, SCOTT, DAVID Control | MANAGING PARTNER | LIMITED PARTNER | 10–25% | Individual |
| ROSENSTEIN, BARRY, STUART Control | DIRECTOR | General partner | Individual |
| ROSENSTEIN, BARRY, STUART Control | FOUNDER & EXECUTIVE CHAIRMAN | LIMITED PARTNER | 10–25% | Individual |
| HUNTER, RYAN, MATTHEW | CHIEF FINANCIAL OFFICER | Less than 5% | Individual |
| YOUNG, JAY, HYUN | CHIEF OPERATING OFFICER | Less than 5% | Individual |
Quarter-over-quarter changes
Changes in reported position value vs the prior 13F, so price moves count too, not just shares bought or sold.
Top Adds (vs prior quarter)
- MERCURY SYS INC$184.8M +61.7%
- ALKAMI TECHNOLOGY INC$37.2M +43.7%
- STATE STR SPDR S&P 500 ETF T$32.6M +14.6%
- LAMB WESTON HLDGS INC$21.3M +10.1%
- RAPID7 INC$17.5M +47.1%
JANA Partners Management, LP Holdings (2026-06-30)
Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).
| # | Issuer | Symbol | CUSIP | Value | Weight | Shares | Type |
|---|---|---|---|---|---|---|---|
| 1 | MERCURY SYS INC | MRCY | 589378108 | $484.3M | 25.46% | 3,958,849 | SH |
| 2 | COOPER COS INC | COO | 216648501 | $256.9M | 13.50% | 3,582,480 | SH |
| 3 | STATE STR SPDR S&P 500 ETF T | SPY | 78462F103 | $256.1M | 13.46% | 342,965 | SH |
| 4 | LAMB WESTON HLDGS INC | LW | 513272104 | $232.9M | 12.25% | 5,394,635 | SH |
| 5 | FISERV INC | FISV | 337738108 | $179.6M | 9.44% | 3,662,080 | SH |
| 6 | MARKEL GROUP INC | MKL | 570535104 | $149.9M | 7.88% | 76,743 | SH |
| 7 | ALKAMI TECHNOLOGY INC | ALKT | 01644J108 | $122.3M | 6.43% | 6,747,707 | SH |
| 8 | SIX FLAGS ENTERTAINMENT CORP | FUN | 83001C108 | $87.7M | 4.61% | 4,116,099 | SH |
| 9 | EVERPURE INC | P | 74624M102 | $77.9M | 4.10% | 989,196 | SH |
| 10 | RAPID7 INC | RPD | 753422104 | $54.7M | 2.87% | 6,749,936 | SH |
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-06-30 | 2026-08-14 | $1.90B | 10 | 0000902664-26-003486 |
| 2026-03-31 | 2026-05-15 | $1.61B | 10 | 0000902664-26-002515 |
| 2026-03-31 | 2026-06-30 | $61.5M | 1 | 0000902664-26-002957 |
| 2025-12-31 | 2026-02-17 | $1.92B | 12 | 0000902664-26-001069 |
| 2025-09-30 | 2025-11-14 | $2.07B | 12 | 0000902664-25-005066 |
24TH FLOOR
NEW YORK, NY 10106