JANA Partners
JANA Partners Management, LP · CIK 0001998597 · NEW YORK, NY · Quarter end: 2026-06-30 · Filed on: 2026-08-14 · Open the SEC source ↗Activist Investor
Portfolio Value (AUM)Total value of the fund's US stock portfolio reported to the SEC.
$1.90B
2026 Q2
Positions
10
Top-10 ConcentrationHow much of the portfolio sits in the 10 largest holdings. High = concentrated bets.
100.0%
Est. Net Flow (Q)
—
2026 Q2
Top Holdings
MRCY
MERCURY SYS INC
25.5%
COO
COOPER COS INC
13.5%
SPY
STATE STR SPDR S&P 500 ETF T
13.5%
LW
LAMB WESTON HLDGS INC
12.2%
FISV
FISERV INC
9.4%
MKL
MARKEL GROUP INC
7.9%
ALKT
ALKAMI TECHNOLOGY INC
6.4%
FUN
SIX FLAGS ENTERTAINMENT CORP
4.6%
New / Increased
No prior quarter data
Reduced / Exited
No prior quarter data
Related managers
Five closest superinvestors by Jaccard overlap of tickers held in the latest quarter (computed nightly).
| Manager | Overlap | Shared holdings |
|---|---|---|
| Greenlea Lane Capital (Josh Tarasoff) | 5.3% | MKL |
| Sachem Head Capital Management | 3.6% | FUN |
| Giverny Capital | 3.4% | MKL, SPY |
| Starboard Value | 3.3% | LW |
| Harris Associates (Bill Nygren) | 2.2% | COO, FISV, SPY |
Read the 2026-Q2 quarterly report · 13F Filing Calendar
13F data shows quarter-end positions, is delayed by up to 45 days and covers only long positions in US-listed securities; short positions, most derivatives and non-US assets are not reported.