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Livermore
Livermore
ZHEN

Maple Rock Capital Partners Inc.

SEC CIK
0001658363
Latest filing
Aug 14, 2026

The latest 13F from Maple Rock Capital Partners Inc. covers Q2 2026 (filed Aug 14, 2026): 51 long positions worth $5.10B. The top 10 holdings make up 53.0% of the portfolio, and the largest is Western Digital Corp (WDC) at 17.0%. Livermore has 22 filings on Form 13F from this institution, going back to Q1 2021.

What changed in Q2 2026

Share counts compared with Q1 2026: how many positions were new, added to, reduced or sold out, and the biggest buys and sells. Dollar amounts are estimated at the quarter-end prices implied by the filing.

Full comparison
New
11
Est. +$554.4M
Added
25
Est. +$1.12B
Reduced
8
Est. −$861.5M
Sold out
4
Est. −$121.0M

Top 5 holdings

Share of this quarter's portfolio value

  1. WDCWestern Digital Corp
    17.0%$867.3MHistory
  2. STXSeagate Technology Holdings plc
    5.7%$290.6MHistory
  3. UNHUnitedHealth Group Inc
    5.6%$283.1MHistory
  4. HUMHumana Inc
    4.9%$249.6MHistory
  5. ICLRIcon PLC
    4.1%$208.4MHistory

Share of portfolio

Top 5 holdings and the other 46 positions, by share of portfolio value

  1. WDC17.0%
  2. STX5.7%
  3. UNH5.6%
  4. HUM4.9%
  5. ICLR4.1%
  6. Other 46 positions62.8%

Biggest buys

New and added positions, by estimated amount bought

  1. UNHUnitedHealth Group Inc
    +$193.6MAddedHistory
  2. ICLRIcon PLC
    +$150.1MAddedHistory
  3. SWSmurfit Westrock plc
    +$120.7MNewHistory
  4. HUMHumana Inc
    +$112.6MAddedHistory
  5. NUENucor Corp
    +$110.7MAddedHistory

Largest weight increases

New and added positions, by percentage points of the portfolio gained

  1. UNHUnitedHealth Group Inc
    +3.65 pp1.9% → 5.6%History
  2. HUMHumana Inc
    +2.95 pp1.9% → 4.9%History
  3. ICLRIcon PLC
    +2.88 pp1.2% → 4.1%History
  4. SWSmurfit Westrock plc
    +2.37 pp0.0% → 2.4%History
  5. NUENucor Corp
    +2.04 pp0.6% → 2.7%History

Biggest sells

Reduced and sold-out positions, by estimated amount sold

  1. SNDKSandisk Corp
    −$374.2MReducedHistory
  2. STXSeagate Technology Holdings plc
    −$224.7MReducedHistory
  3. CLFCleveland-Cliffs Inc.
    −$165.8MReducedHistory
  4. GTGoodyear Tire & Rubber Co
    −$38.6MSold outHistory
  5. BTGB2GOLD Corp
    −$37.0MSold outHistory

Largest weight decreases

Reduced and sold-out positions, by percentage points of the portfolio lost

  1. EQXEquinox Gold Corp.
    −5.79 pp9.1% → 3.3%History
  2. CLFCleveland-Cliffs Inc.
    −5.14 pp5.7% → 0.6%History
  3. SNDKSandisk Corp
    −3.36 pp3.4% → 0.1%History
  4. JDJD.com, Inc.
    −1.58 pp2.9% → 1.3%History
  5. GTGoodyear Tire & Rubber Co
    −1.25 pp1.3% → 0.0%History

Metrics

13F metrics for Q2 2026, computed only from the numbers in the filings. Definitions below.

Portfolio value
$5.10B
+$2.03B (+65.9%) vs. prior quarter
Positions
51
+7 vs. prior quarter
Top 10 concentration
53.0%
Top 10 as share of value
Turnover
24.0%
Q2 2026, one quarter
Average holding period
7.7 quarters
Weighted by value

How these are calculated

  • Portfolio value: the market value of all long positions in the 13F, as reported at quarter end, excluding options.
  • Top 10 concentration: the combined value of the 10 largest positions as a share of portfolio value.
  • Turnover: the smaller of this quarter's estimated purchases and estimated sales, divided by the average of this and last quarter's portfolio value. Estimates multiply the change in shares by the quarter-end price implied by the filing (market value divided by shares); new positions use this quarter's value and sold-out positions last quarter's. Only positions reported in shares count, and it is not calculated when the previous quarter was not filed.
  • Average holding period: how many consecutive quarters each current position has been held (including this one; a quarter without the position or without a filing starts the count over), weighted by this quarter's value. Counting starts with the first 13F in Livermore (Q1 2021), so positions held before then are understated.

13F filings by quarter

22 quarters, going back to Q1 2021. Bars show each quarter's 13F portfolio value; quarters without a filing are left blank.

Peak $5.10B (Q2 2026)

Q1 2021: $689.2MQ2 2021: $665.3MQ3 2021: $713.9MQ4 2021: $802.9MQ1 2022: $905.1MQ2 2022: $866.1MQ3 2022: $1.08BQ4 2022: $678.8MQ1 2023: $1.02BQ2 2023: $785.3MQ3 2023: $859.4MQ4 2023: $1.28BQ1 2024: $1.58BQ2 2024: $1.46BQ3 2024: $1.76BQ4 2024: $1.37BQ1 2025: $1.37BQ2 2025: $2.00BQ3 2025: $2.48BQ4 2025: $3.03BQ1 2026: $3.07BQ2 2026: $5.10B
Q1 2021Q2 2026
13F filings of Maple Rock Capital Partners Inc. by quarter
QuarterFiledPositionsValueTop 3 holdingsChangesFiling
Q2 2026Aug 14, 202651$5.10BWDCSTXUNHvs. Q1 2026SEC
Q1 2026May 15, 202644$3.07BWDCEQXSTXvs. Q4 2025SEC
Q4 2025Feb 17, 202638$3.03BWDCEQXSTXvs. Q3 2025SEC
Q3 2025Nov 14, 202540$2.48BWDCEQXSTXvs. Q2 2025SEC
Q2 2025Aug 14, 202539$2.00BWDCSTXTFIIvs. Q1 2025SEC
Q1 2025May 15, 202535$1.37BWDCTFIIBABAvs. Q4 2024SEC
Q4 2024Feb 14, 202529$1.37BWDCTEVATLNvs. Q3 2024SEC
Q3 2024Nov 14, 202428$1.76BWDCVSTJDvs. Q2 2024SEC
Q2 2024Aug 14, 202427$1.46BWDCSPRVSTvs. Q1 2024SEC
Q1 2024May 15, 202429$1.58BWDCSPRVSTvs. Q4 2023SEC
Q4 2023Feb 14, 202427$1.28BWDCSPRARCHvs. Q3 2023SEC
Q3 2023Nov 14, 202323$859.4MWDCARCHKOSvs. Q2 2023SEC
Q2 2023Aug 14, 202320$785.3MSPRWDCSUvs. Q1 2023SEC
Q1 2023May 15, 202327$1.02BSPRKOSWDCvs. Q4 2022SEC
Q4 2022Feb 14, 202319$678.8MKOSWDCSUvs. Q3 2022SEC
Q3 2022Nov 14, 202226$1.08BOVVTRIPWDCvs. Q2 2022SEC
Q2 2022Aug 15, 202222$866.1MARCHVSTSPRvs. Q1 2022SEC
Q1 2022May 16, 202221$905.1MARCHSPRASTLvs. Q4 2021SEC
Q4 2021Feb 14, 202224$802.9MARCHGPNSPRvs. Q3 2021SEC
Q3 2021Nov 15, 202122$713.9MOVVARCHVTLEvs. Q2 2021SEC
Q2 2021Aug 16, 202120$665.3MOVVWDCTROXvs. Q1 2021SEC
Q1 2021May 17, 202122$689.2MSMWDCTROX–SEC

13D and 13G filings

Companies where Maple Rock Capital Partners Inc. reports owning 5% or more on Schedule 13D or 13G, and its latest filings.

Current stakes of 5% or more

2 companies, largest stake first.

Companies where Maple Rock Capital Partners Inc. owns 5% or more
CompanyLatest formStakeChangeFirst filedLatest filingFiling
ASTLAlgoma Steel Group Inc.13G/A15.10%15.9M shares+1.80 ppfrom 13.30%Feb 14, 20238 filingsMay 15, 2026SEC
WGOWinnebago Industries Inc13G5.50%1.56M sharesNewAug 14, 20261 filingAug 14, 2026SEC

Latest filings

20 filings on file made by Maple Rock Capital Partners Inc. or listing it as a reporting person, newest first.

Schedule 13D and 13G filings by Maple Rock Capital Partners Inc.
CompanyFiled (ET)FormStakeChangeEvent dateFiling
WGOWinnebago Industries IncAug 14, 20264:07 PM ET13G5.50%1.56M sharesNewJun 30, 2026SEC
ASTLAlgoma Steel Group Inc.May 15, 20265:08 PM ET13G/A15.10%15.9M shares+1.80 ppfrom 13.30%Mar 31, 2026SEC
ASTLAlgoma Steel Group Inc.Nov 7, 20254:12 PM ET13G/A13.30%14.0M shares+3.40 ppfrom 9.90%Oct 31, 2025SEC
ASTLAlgoma Steel Group Inc.Aug 28, 20256:57 PM ET13G9.90%10.4M shares0.00 ppfrom 9.90%Aug 28, 2025SEC
ASTLAlgoma Steel Group Inc.Aug 14, 20258:48 PM ET13D/A9.90%10.4M shares+2.70 ppfrom 7.20%Aug 12, 2025SEC
ASTLAlgoma Steel Group Inc.May 5, 20257:07 PM ET13D/A7.20%7.55M shares–May 1, 2025SEC
HUYAHUYA Inc.Feb 14, 20255:04 PM ET13G/A0.00%0 shares–Below 5%Dec 31, 2024SEC
GRPNGroupon, Inc.Nov 14, 202413G/AOld format–––SEC
HUYAHUYA Inc.Nov 14, 202413GOld format–New–SEC
ASTLAlgoma Steel Group Inc.Oct 25, 202413DOld format–––SEC
GRPNGroupon, Inc.Feb 14, 202413G/AOld format–––SEC
ASTLAlgoma Steel Group Inc.Feb 14, 202413G/AOld format–––SEC
GRPNGroupon, Inc.Feb 14, 202313GOld format–––SEC
ASTLAlgoma Steel Group Inc.Feb 14, 202313GOld format–New–SEC
ARCHArch Resources, Inc.Feb 14, 202313G/AOld format–––SEC
GRPNGroupon, Inc.Dec 9, 202213G/AOld format–––SEC
GRPNGroupon, Inc.Aug 15, 202213GOld format–New–SEC
SMSM Energy CoFeb 14, 202213G/AOld format–––SEC
ARCHArch Resources, Inc.Feb 14, 202213GOld format–New–SEC
SMSM Energy CoFeb 16, 202113GOld format–New–SEC