How We Invest

13F FILER • MATTHEW HALBOWER

Pentwater Capital

Matthew Halbower — Pentwater Capital Management LP

No writing by this manager has been read and indexed yet, so this page carries the filings only. Holdings come straight from the Form 13F-HR on EDGAR.

90

Positions

$16.4B

Reported Value

66.5%

In Top 10

—

Claims Indexed

Largest reported positions

PENTWATER CAPITAL MANAGEMENT LP • CIK 0001425851 • 2026-06-30 • FILED 2026-08-14

WHAT CHANGED THIS QUARTER

In its Q2 2026 13F, filed Aug 14, 2026, Pentwater Capital reported 90 positions worth $12.5B in US-listed stock. The largest stock position is Electronic Arts Inc at 16.9% of the reported book, and the ten largest lines of any type make up 66.5% of it.

It opened 42 new positions, the largest stock positions being Roku Inc ($597.5M), Organon & Co ($245.1M) and Dominion Energy Inc ($239.0M), and exited 44, the largest stock exits being Masimo Corp ($564.9M last quarter), Hologic Inc ($340.2M last quarter) and Arcellx Inc ($329.5M last quarter).

Among positions it already held, the biggest increases by share count were Tenet Healthcare Corp (+512%), Caesars Entertainment Inc Ne (+333%) and Paramount Skydance Corp (+193%), and the biggest cuts were Avis Budget Group Inc (−64%), Teck Resources Ltd (−14%) and Norfolk Southn Corp (−14%).

Largest reported positions, quarter ended 2026-06-30
IssuerValueWeightShares QoQ
ELECTRONIC ARTS INC$2.8B16.9%+5%
BOEING CO$1.3B8.2%-12%
WARNER BROS DISCOVERY INC$1.3B7.8%-5%
STATE STR SPDR S&P 500 ETF T (Put)$1.1B6.5%-53%
KENVUE INC$977.1M6.0%-2%
NORFOLK SOUTHN CORP$873.0M5.3%-14%
BOEING CO (Put)$828.0M5.1%-24%
UNITEDHEALTH GROUP INC (Call)$777.2M4.8%-34%
ROKU INC$597.5M3.6%New
ECHOSTAR CORP$391.8M2.4%+64%
AVIS BUDGET GROUP INC$371.5M2.3%-64%
TXNM ENERGY INC$368.4M2.3%+132%
TECK RESOURCES LTD$354.4M2.2%-14%
CAESARS ENTERTAINMENT INC NE$346.0M2.1%+333%
GEO GROUP INC$312.7M1.9%+11%
ORGANON & CO$245.1M1.5%New
DOMINION ENERGY INC$239.0M1.5%New
DIGITALBRIDGE GROUP INC$198.8M1.2%+7%
SURGERY PARTNERS INC$195.4M1.2%-8%
APOGEE THERAPEUTICS INC$189.1M1.2%New

20 of 90 positions. 23.4% of reported value is options, where the figure is the notional value of the underlying rather than money spent. A 13F covers long US-listed positions at a quarter end only — no shorts, leverage, cash, ordinary bonds or private holdings — and is 45 days old on publication.

NEW POSITIONS

  • Roku Inc$597.5M · 3.6%
  • Organon & Co$245.1M · 1.5%
  • Dominion Energy Inc$239.0M · 1.5%
  • Apogee Therapeutics Inc$189.1M · 1.2%
  • Carnival Corp Ltd$163.0M · 1.0%

EXITS

  • Masimo Corp$564.9M last quarter
  • Hologic Inc$340.2M last quarter
  • Arcellx Inc$329.5M last quarter
  • Centessa Pharmaceuticals Plc$324.5M last quarter
  • Netflix Inc.$296.9M last quarter

QUESTIONS PEOPLE ASK

What are Pentwater Capital's largest holdings?

OPEN
As of Jun 30, 2026, the three largest stock positions are Electronic Arts Inc (16.9%), Boeing Co (8.2%) and Warner Bros Discovery Inc (7.8%), together 32.9% of the reported book.

How big is Pentwater Capital's 13F portfolio?

OPEN
The Q2 2026 13F, filed Aug 14, 2026, reports 90 positions worth $16.4B. The ten largest make up 66.5% of it. 23.4% of that value is options, reported at the notional value of the underlying rather than money spent.

What did Pentwater Capital buy and sell in Q2 2026?

OPEN
It opened 42 new positions, the largest stock positions being Roku Inc ($597.5M), Organon & Co ($245.1M) and Dominion Energy Inc ($239.0M), and exited 44, the largest stock exits being Masimo Corp ($564.9M last quarter), Hologic Inc ($340.2M last quarter) and Arcellx Inc ($329.5M last quarter). Among positions it already held, the biggest increases by share count were Tenet Healthcare Corp (+512%), Caesars Entertainment Inc Ne (+333%) and Paramount Skydance Corp (+193%), and the biggest cuts were Avis Budget Group Inc (−64%), Teck Resources Ltd (−14%) and Norfolk Southn Corp (−14%).

When is Pentwater Capital's next 13F due?

OPEN
The Q3 2026 13F is due Nov 16, 2026. Forty-five days after the quarter ends is November 14, 2026 (Saturday), so the deadline moves to the next business day. Matthew Halbower's filing usually lands close to the deadline.

Filers with overlapping books