Barry Rosenstein JANA Partners Management
Barry Rosenstein is the founder of JANA Partners, an activist and event-driven investment firm. JANA is known for campaigns seeking strategic change, improved capital returns, and better operational execution at public companies. Rosenstein’s efforts have spanned consumer, industrial, and technology-related businesses over many years.
Top Buys
| Rank | Stock | Value |
|---|---|---|
| 1 |
FISV
Fiserv Inc
FISV
|
+$188M |
| 2 |
Cooper Companies
COO
|
+$81.2M |
| 3 |
Alkami Technology
ALKT
|
+$66.2M |
| 4 |
Rapid7
RPD
|
+$3.98M |
| 5 |
State Street SPDR S&P 500 ETF Trust
SPY
|
+$3.18M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Trimble
TRMB
|
+$154M |
| 2 |
Markel Group
MKL
|
+$134M |
| 3 |
Mercury Systems
MRCY
|
+$74.4M |
| 4 |
Freshpet
FRPT
|
+$27.8M |
| 5 |
EHAB
Enhabit
EHAB
|
+$405K |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Consumer Staples | 19.83% |
| 2 | Technology | 19.06% |
| 3 | Industrials | 18.84% |
| 4 | Healthcare | 16.01% |
| 5 | Financials | 9.08% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
|
1
Mercury Systems
MRCY
$5.49B
| $362M | 18.84% |
4,959,481
-1,000,000
| -17% | -$74.4M |
|
|
2
Cooper Companies
COO
$14.9B
| $288M | 15.01% |
3,519,620
+1,085,013
| +45% | +$81.2M |
|
|
3
State Street SPDR S&P 500 ETF Trust
SPY
$809B
| $267M | 13.89% |
391,337
+4,700
| +1% | +$3.18M |
|
4
Lamb Weston
LW
$7.38B
| $210M | 10.92% |
5,008,635
| – | – |
|
|
5
Markel Group
MKL
$22.2B
| $175M | 9.08% |
81,219
-66,192
| -45% | -$134M |
|
|
FISV
6
Fiserv Inc
FISV
$28B
| $151M | 7.85% |
+2,245,520
| New | +$188M |
|
|
THS
7
DELISTED
Treehouse Foods
THS
| $137M | 7.15% |
5,821,337
| – | – |
|
|
8
Alkami Technology
ALKT
$2.18B
| $113M | 5.88% |
4,894,665
+3,002,252
| +159% | +$66.2M |
|
|
9
Rapid7
RPD
$799M
| $103M | 5.33% |
6,743,653
+241,545
| +4% | +$3.98M |
|
10
Cedar Fair
FUN
$1.71B
| $63.1M | 3.29% |
4,116,099
+66,159
| +2% | +$1.2M |
|
|
11
Freshpet
FRPT
$3.55B
| $34M | 1.77% |
557,390
-490,746
| -47% | -$27.8M |
|
|
EHAB
12
DELISTED
Enhabit
EHAB
| $19.3M | 1% |
2,090,412
-46,733
| -2% | -$405K |
|
|
13
Trimble
TRMB
$14B
| – | – |
-1,881,399
| Closed | -$154M |
|
Similar funds
Barry Rosenstein's Q4 2025 Portfolio in Review
As of Q4 2025, Barry Rosenstein held 13 positions worth $1.92B, down 7% from $2.07B the previous quarter. Its ten largest holdings account for 97% of the portfolio.
Barry Rosenstein's Q4 2025 filing shows 1 new, 5 increased, 4 reduced and 1 closed positions. Its largest new stake was Fiserv Inc: 2,245,520 shares worth $151M. The largest sale was Trimble, an estimated $154M.
By sector, the portfolio is most concentrated in Consumer Staples at 20% of assets, down from 23% a quarter earlier, followed by Technology and Industrials.
- Barry Rosenstein's largest Q4 2025 buy was Fiserv Inc: 2,245,520 shares worth $151M.
- Barry Rosenstein added most to Cooper Companies in Q4 2025, an estimated $81.2M increase.
- Barry Rosenstein's biggest Q4 2025 reduction was Markel Group, cutting an estimated $134M.
- Barry Rosenstein fully exited Trimble in Q4 2025, selling an estimated $154M.
- Barry Rosenstein's ten largest holdings make up 97% of its $1.92B portfolio in Q4 2025.
- Barry Rosenstein opened 1 new position and closed 1 in Q4 2025.
- Barry Rosenstein's portfolio value fell 7% quarter-over-quarter to $1.92B.
Based on JANA Partners Management's 13F filing for Q4 2025, filed 17 Feb 2026.