William Harnisch Peconic Partners
William Harnisch is the founder of Peconic Partners, a concentrated investment firm known for high-conviction equity positions. The firm’s portfolio often differs sharply from broad market benchmarks, reflecting a willingness to concentrate capital. Harnisch’s disclosures are tracked by investors interested in bold, research-driven concentration.
Top Buys
| Rank | Stock | Value |
|---|---|---|
| 1 |
State Street Utilities Select Sector SPDR ETF
XLU
|
+$79.7M |
| 2 |
First Solar
FSLR
|
+$44.3M |
| 3 |
Range Resources
RRC
|
+$30.2M |
| 4 |
Alphabet (Google) Class A
GOOGL
|
+$29.5M |
| 5 |
EQT Corp
EQT
|
+$25.9M |
Top Sells
| Rank | Stock | Value |
|---|---|---|
| 1 |
Quanta Services
PWR
|
+$96.6M |
| 2 |
Caesars Entertainment
CZR
|
+$20.1M |
| 3 |
NextEra Energy
NEE
|
+$460K |
Sector Composition
| Rank | Sector | Weight |
|---|---|---|
| 1 | Industrials | 90.47% |
| 2 | Technology | 3.02% |
| 3 | Energy | 1.94% |
| 4 | Communication Services | 1.02% |
| 5 | Consumer Discretionary | 0.94% |
| Name | Market Value | Portfolio Weight | Shares or Principal |
Change in Stake | Capital Flow | |
|---|---|---|---|---|---|---|
|
1
Quanta Services
PWR
$96.1B
| $1.89B | 60.56% |
4,996,649
-300,916
| -6% | -$96.6M |
|
2
Dycom Industries
DY
$11.8B
| $933M | 29.91% |
3,817,825
+105,586
| +3% | +$20.8M |
|
|
3
State Street Utilities Select Sector SPDR ETF
XLU
$22.2B
| $81.7M | 2.62% |
+2,000,000
| New | +$79.7M |
|
|
4
First Solar
FSLR
$23B
| $49.7M | 1.59% |
+300,000
| New | +$44.3M |
|
|
5
Range Resources
RRC
$9.59B
| $32.5M | 1.04% |
+800,000
| New | +$30.2M |
|
|
6
Alphabet (Google) Class A
GOOGL
$4.22T
| $31.7M | 1.02% |
+180,000
| New | +$29.5M |
|
7
Shoals Technologies Group
SHLS
$1.19B
| $29.6M | 0.95% |
6,975,186
+3,095,186
| +80% | +$13.5M |
|
8
Amazon
AMZN
$2.79T
| $29.4M | 0.94% |
133,980
+130,000
| +3,266% | +$25.7M |
|
|
9
EQT Corp
EQT
$33.6B
| $28M | 0.9% |
+480,000
| New | +$25.9M |
|
10
Array Technologies
ARRY
$722M
| $14.3M | 0.46% |
2,420,783
+20,783
| +0.9% | +$126K |
|
11
Nextpower Inc
NXT
$13.1B
| $544K | 0.02% |
+10,000
| New | +$502K |
|
|
12
Caesars Entertainment
CZR
$6.06B
| – | – |
-804,844
| Closed | -$20.1M |
|
|
13
NextEra Energy
NEE
$174B
| – | – |
-6,485
| Closed | -$460K |
|
Similar funds
William Harnisch's Q2 2025 Portfolio in Review
As of Q2 2025, William Harnisch held 13 positions worth $3.12B, up 59% from $1.96B the previous quarter. Its ten largest holdings account for 100% of the portfolio.
William Harnisch deployed $153M of net new capital in Q2 2025, opening 6 new positions and adding to 4 existing holdings. Its largest new stake was State Street Utilities Select Sector SPDR ETF: 2,000,000 shares worth $81.7M.
By sector, the portfolio is most concentrated in Industrials at 90% of assets, down from 98% a quarter earlier, followed by Technology and Energy.
On the sell side, the largest reduction was Quanta Services, an estimated $96.6M trimmed.
- William Harnisch's largest Q2 2025 buy was State Street Utilities Select Sector SPDR ETF: 2,000,000 shares worth $81.7M.
- William Harnisch added most to Amazon in Q2 2025, an estimated $25.7M increase.
- William Harnisch's biggest Q2 2025 reduction was Quanta Services, cutting an estimated $96.6M.
- William Harnisch fully exited Caesars Entertainment in Q2 2025, selling an estimated $20.1M.
- William Harnisch's ten largest holdings make up 100% of its $3.12B portfolio in Q2 2025.
- William Harnisch opened 6 new positions and closed 2 in Q2 2025.
- William Harnisch's portfolio value rose 59% quarter-over-quarter to $3.12B.
Based on Peconic Partners's 13F filing for Q2 2025, filed 14 Aug 2025.