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Maple Rock Capital Partners Inc. — 13F Holdings & Portfolio

CIK 1658363 · latest 13F-HR filed 2026-08-14

Backtest portfolio

Maple Rock Capital Partners Inc. manages $5.10B in 13F-reported U.S. long-equity assets across 51 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are WDC (17.01%), STX (5.70%), UNH (5.55%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 11 new positions and exited 4; 28 existing positions rose in reported value and 10 fell.

AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.

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AUM
$5.10B

Long-equity book

Holdings
51

Distinct positions

Period
2026-06-30

Filed 2026-08-14

Q/Q Activity
+11 / −4 / ↑28 / ↓10

vs 2026-03-31

Portfolio charts

Latest quarter's book, what changed, and how the portfolio has evolved across filings.

Portfolio map

Q2 26
WDC17.0% · -3%STX5.7% · -44%UNH5.6% · +216%HUM4.9% · +82%ICLR4.1% · +258%TFII4.0% · +4%EQX3.3% · -10%AAP3.0% · +86%BKD2.8% · +9%NUE2.7% · +424%BTI2.6% · +36%MT2.6% · +55%CVS2.4% · +14%SW2.4% · newLPX2.3% · +37%CNC1.7% · +110%RKT1.7% · +77%AA1.6% · +75%ARCB1.5% · +32%ELV1.5% · +209%XPO1.4% · +10%RXO1.4% · newASTL1.3% · +6%FDXF1.3% · newJD1.3% · -12%WERN1.2% · +147%TPB1.1% · +58%WAB1.1% · 0%MOS1.1% · newMOH1.1% · +43%FBIN1.1% · +105%LKQ1.1% · 0%RUN1.0% · +23%WGO1.0% · +33%RMBS0.9% · newNGVT0.9% · 0%GPK0.8% · newTECK0.8% · newGM0.8% · newTHO0.7% · 0%TLN0.6% · newLVS0.6% · 0%LYFT0.6% · -50%CLF0.6% · -85%KNX0.6% · 0%ASO0.5% · -30%AMZN0.5% · newRYAM0.5% · 0%HCC0.4% · +77%IP0.2% · newSNDK0.1% · -99%

Box size = position value; colour = change in share count vs the prior quarter (green added, red trimmed, blue new). Rows split across managers or share classes are combined. Click a box for the stock.

Sector mix

% of 13F value

Sectors from each company's SIC code; funds and ETFs grouped separately.

Biggest buys and sells

Q1 26 → Q2 26

Estimated from the change in shares held × the quarter-end price, so price moves alone don't count as buying. New and exited positions are included.

13F assets and positions

4 quarters

Total reported 13F value (bars) and number of positions (line) each quarter. Value changes include market moves.

Top positions over time

reported value

The eight largest current positions, valued at each quarter end.

Concentration

top 10 = 53%

Cumulative share of the portfolio held in the largest N positions.

Firm Profile & Key People

As of the firm’s regulatory filing dated Mar 31, 2026.

Assets Under Management
$6.34B
Discretionary
$6.34B
Employees
16
Accounts
3
Address
21 ST. CLAIR AVENUE EAST
SUITE 1100
TORONTO M4T 1L9
Canada
Phone
(416) 619-0705
Website
This firm reports 2 disclosure items on its registration.
Name Title / Status Ownership Type
LANE, STEPHEN, DENGLER ControlCHIEF FINANCIAL OFFICER, CHIEF COMPLIANCE OFFICER
since Jun 2018
Less than 5%Individual
MAJIC, XAVIER, GEORGE ControlCHIEF EXECUTIVE OFFICER, CHIEF INVESTMENT OFFICER
since Apr 2014
Less than 5%Individual
THREE SISTERS HOLDINGS INC. ControlSOLE SHAREHOLDER
since Mar 2021
75% or moreForeign Entity
MAJIC, XAVIER, GEORGE Control
Indirect owner via THREE SISTERS HOLDINGS INC.
SOLE SHAREHOLDER
since Mar 2021
75% or moreIndividual
Ownership & leadership changes · 5 filings with changes since Nov 24, 2014

From the firm’s regulatory filings, newest first. Dates are filing dates: a filing that no longer lists someone does not say when they left.

Mar 30, 2021 filing
  • AddedMAJIC, XAVIER, GEORGE · SOLE SHAREHOLDER · 75% or more · indirect via THREE SISTERS HOLDINGS INC. · control person
  • AddedTHREE SISTERS HOLDINGS INC. · SOLE SHAREHOLDER · 75% or more · control person
  • ChangedMAJIC, XAVIER, GEORGE · ownership 75% or more → Less than 5%
Jul 9, 2018 filing
  • No longer listedSPAIN, MARCUS, JOHN · CHIEF FINANCIAL OFFICER · Less than 5% · control person · listed since May 2014
  • ChangedLANE, STEPHEN, DENGLER · title CHIEF COMPLIANCE OFFICER → CHIEF FINANCIAL OFFICER, CHIEF COMPLIANCE OFFICER
  • ChangedMAJIC, XAVIER, GEORGE · ownership Less than 5% → 75% or more
Jun 14, 2018 filing
  • AddedLANE, STEPHEN, DENGLER · CHIEF COMPLIANCE OFFICER · Less than 5% · control person
  • ChangedSPAIN, MARCUS, JOHN · title CHIEF FINANCIAL OFFICER, CHIEF COMPLIANCE OFFICER → CHIEF FINANCIAL OFFICER
Mar 30, 2018 filing
  • No longer listedLIZARD RANGE HOLDINGS INC. · OWNER · 75% or more · control person · listed since Dec 2016
  • No longer listedMAJIC, XAVIER, GEORGE · OWNER · 75% or more · indirect via LIZARD RANGE HOLDINGS INC. · control person · listed since Nov 2016
  • ChangedSPAIN, MARCUS, JOHN · title CHIEF FINANCIAL OFFICER AND CHIEF COMPLIANCE OFFICER → CHIEF FINANCIAL OFFICER, CHIEF COMPLIANCE OFFICER
Mar 31, 2017 filing
  • No longer listedKIPP, LENNARD, CHRISTOPHER · SHAREHOLDER, MANAGING DIRECTOR, HEAD OF RESEARCH · 25–50% · control person · listed since Apr 2014
  • AddedLIZARD RANGE HOLDINGS INC. · OWNER · 75% or more · control person
  • AddedMAJIC, XAVIER, GEORGE · OWNER · 75% or more · indirect via LIZARD RANGE HOLDINGS INC. · control person
  • ChangedMAJIC, XAVIER, GEORGE · title SHAREHOLDER, CHIEF EXECUTIVE OFFICER, CHIEF INVESTMENT OFFICER → CHIEF EXECUTIVE OFFICER, CHIEF INVESTMENT OFFICER; ownership 50–75% → Less than 5%
Nov 24, 2014 filing (earliest on record)
  • ListedKIPP, LENNARD, CHRISTOPHER · SHAREHOLDER, MANAGING DIRECTOR, HEAD OF RESEARCH · 25–50% · control person
  • ListedMAJIC, XAVIER, GEORGE · SHAREHOLDER, CHIEF EXECUTIVE OFFICER, CHIEF INVESTMENT OFFICER · 50–75% · control person
  • ListedSPAIN, MARCUS, JOHN · CHIEF FINANCIAL OFFICER AND CHIEF COMPLIANCE OFFICER · Less than 5% · control person

Quarter-over-quarter changes

Changes in reported position value vs the prior 13F, so price moves count too, not just shares bought or sold.

Top Adds (vs prior quarter)

Show all 28 →

Top Trims

Show all 10 →

New Positions

Show all 11 →

Exited Positions

Show all 4 →

Maple Rock Capital Partners Inc. Holdings (2026-06-30)

Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).

# Issuer Symbol CUSIP Value Weight Shares Type
1 WESTERN DIGITAL CORP WDC 958102105 $867.3M 17.01% 1,357,834 SH
2 SEAGATE TECHNOLOGY HLDNGS PL STX G7997R103 $290.6M 5.70% 301,162 SH
3 UNITEDHEALTH GROUP INC UNH 91324P102 $283.1M 5.55% 681,100 SH
4 HUMANA INC HUM 444859102 $249.6M 4.89% 628,251 SH
5 ICON PUB LTD CO ICLR G4705A100 $208.4M 4.09% 1,199,600 SH
6 TFI INTERNATIONAL INC TFII 87241L109 $203.6M 3.99% 1,418,409 SH
7 EQUINOX GOLD CORP EQX 29446Y502 $170.4M 3.34% 17,531,248 SH
8 ADVANCE AUTO PARTS INC AAP 00751Y106 $150.6M 2.95% 2,421,040 SH
9 BROOKDALE SR LIVING INC BKD 112463104 $143.0M 2.80% 8,888,148 SH
10 NUCOR CORP NUE 670346105 $136.8M 2.68% 614,000 SH
11 BRITISH AMERN TOB PLC BTI 110448107 $133.8M 2.62% 2,166,000 SH
12 ARCELORMITTAL SA LUXEMBOURG MT 03938L203 $131.9M 2.59% 2,190,860 SH
13 CVS HEALTH CORP CVS 126650100 $123.9M 2.43% 1,197,996 SH
14 SMURFIT WESTROCK PLC SW G8267P108 $120.7M 2.37% 2,608,298 SH
15 LOUISIANA PAC CORP LPX 546347105 $119.7M 2.35% 1,521,859 SH
16 CENTENE CORP DEL CNC 15135B101 $88.7M 1.74% 1,381,879 SH
17 ROCKET COS INC RKT 77311W101 $87.3M 1.71% 5,543,600 SH
18 ALCOA CORP AA 013872106 $82.3M 1.61% 1,577,720 SH
19 ARCBEST CORP ARCB 03937C105 $76.9M 1.51% 535,746 SH
20 ELEVANCE HEALTH INC FORMERLY ELV 036752103 $74.1M 1.45% 191,500 SH
21 XPO INC XPO 983793100 $72.4M 1.42% 352,702 SH
22 RXO INC RXO 74982T103 $71.3M 1.40% 2,583,655 SH
23 ALGOMA STL GROUP INC ASTL 015658107 $68.3M 1.34% 16,861,818 SH
24 FEDEX FGHT HLDG CO INC FDXF 314352105 $68.2M 1.34% 451,700 SH
25 JD.COM INC JD 47215P106 $68.0M 1.33% 2,670,542 SH
26 WERNER ENTERPRISES INC WERN 950755108 $59.6M 1.17% 1,366,167 SH
27 TURNING PT BRANDS INC TPB 90041L105 $58.2M 1.14% 686,800 SH
28 WABTEC WAB 929740108 $58.1M 1.14% 215,400 SH
29 MOSAIC CO MOS 61945C103 $56.8M 1.11% 2,680,000 SH
30 MOLINA HEALTHCARE INC MOH 60855R100 $55.6M 1.09% 243,300 SH
31 FORTUNE BRANDS INNOVATIONS I FBIN 34964C106 $54.7M 1.07% 996,282 SH
32 LKQ CORP LKQ 501889208 $54.4M 1.07% 2,065,565 SH
33 SUNRUN INC RUN 86771W105 $49.4M 0.97% 3,694,548 SH
34 WINNEBAGO INDS INC WGO 974637100 $48.7M 0.96% 1,559,231 SH
35 RAMBUS INC DEL RMBS 750917106 $45.5M 0.89% 342,600 SH
36 INGEVITY CORP NGVT 45688C107 $45.0M 0.88% 603,303 SH
37 GRAPHIC PACKAGING HLDG CO GPK 388689101 $43.3M 0.85% 4,099,800 SH
38 TECK RESOURCES LTD TECK 878742204 $42.7M 0.84% 718,500 SH
39 GENERAL MTRS CO GM 37045V100 $38.5M 0.75% 499,497 SH
40 THOR INDS INC THO 885160101 $34.7M 0.68% 461,864 SH
41 TALEN ENERGY CORP TLN 87422Q109 $30.9M 0.61% 80,300 SH
42 LAS VEGAS SANDS CORP LVS 517834107 $30.6M 0.60% 662,824 SH
43 LYFT INC LYFT 55087P104 $30.1M 0.59% 2,062,351 SH
44 CLEVELAND-CLIFFS INC NEW CLF 185899101 $29.0M 0.57% 3,083,157 SH
45 KNIGHT-SWIFT TRANSN HLDGS IN KNX 499049104 $28.5M 0.56% 366,095 SH
46 ACADEMY SPORTS & OUTDOORS IN ASO 00402L107 $27.6M 0.54% 586,400 SH
47 AMAZON COM INC AMZN 023135106 $25.7M 0.50% 108,000 SH
48 RAYONIER ADVANCED MATLS INC RYAM 75508B104 $25.6M 0.50% 3,256,889 SH
49 WARRIOR MET COAL INC HCC 93627C101 $20.6M 0.40% 253,559 SH
50 INTERNATIONAL PAPER CO IP 460146103 $10.8M 0.21% 284,400 SH
Filing History
Period Filed AUM Holdings Accession
2026-06-30 2026-08-14 $5.10B 51 0001658363-26-000007
2026-03-31 2026-05-15 $3.07B 44 0001658363-26-000005
2025-12-31 2026-02-17 $3.03B 38 0001658363-26-000003
2025-09-30 2025-11-14 $2.53B 41 0001658363-25-000005
Filer Information
Address
21 ST. CLAIR AVENUE EAST, SUITE 1100
TORONTO, A6 M4T 1L9
Phone
(416) 572-3899
Filing Manager
Maple Rock Capital Partners Inc.
Toronto, A6
Signatory
Stephen D. Lane
Chief Financial Officer, Chief Compliance Officer