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SOUTHERNSUN ASSET MANAGEMENT, LLC — 13F Holdings & Portfolio

CIK 1089755 · latest 13F-HR filed 2026-08-14

Backtest portfolio

SOUTHERNSUN ASSET MANAGEMENT, LLC manages $742.8M in 13F-reported U.S. long-equity assets across 29 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are EXTR (7.34%), LPX (6.12%), BOOT (5.94%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 0 new positions and exited 2; 21 existing positions rose in reported value and 5 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
$742.8M

Long-equity book

Holdings
29

Distinct positions

Period
2026-06-30

Filed 2026-08-14

Q/Q Activity
+0 / −2 / ↑21 / ↓5

vs 2026-03-31

Portfolio charts

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

Portfolio map

Q2 26
EXTR7.3% · -27%LPX6.1% · +19%BOOT5.9% · -1%MUSA5.8% · -6%CXT5.7% · +6%DAR5.6% · -2%LOB5.1% · -10%AGCO4.9% · +24%USPH4.9% · +20%DORM4.8% · +7%MSA4.7% · +17%AWI4.3% · +19%EPAC4.1% · +28%BCO4.1% · +1%CSW3.5% · +7%SAM3.1% · +76%MOD2.8% · -30%NGVT2.5% · -3%THO2.4% · +82%KAI2.1% · +13%AEIS1.9% · -18%GNRC1.6% · -17%APG1.4% · -4%VMI1.1% · -18%WSO1.0% · -4%OSK0.9% · +40%BR0.8% · -4%SEIC0.8% · -6%FND0.7% · -4%

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 = 56.3%

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

Firm Profile & Key People
Assets Under Management
$749.4M
Discretionary
$749.4M
Employees
15
Accounts
88
Address
240 MADISON AVENUE
SUITE 800
MEMPHIS, TN 38103
Phone
(901) 341-2700
Website
Name Title / Status Ownership Type
COOK, MICHAEL, WHITMAN ControlCHAIRMAN/PRINCIPAL/MGMT COMM MBR25–50%Individual
COOK, MICHAEL, WHITMAN ControlMEMBER50–75%Individual
COOK, PHILLIP, WHITMAN ControlCHIEF INVESTMENT OFFICER/MANAGING PARTNER/PRINCIPAL/MGMT COMM MBR5–10%Individual
COOK, PHILLIP, WHITMAN ControlMEMBERGeneral partnerIndividual
CROSS, MICHAEL, SCOTT ControlPORTFOLIO MANAGER/PRINCIPAL5–10%Individual
HALLIDAY, WILLIAM, P. ControlCHIEF COMPLIANCE OFFICER/PRINCIPAL/MGMT COMM MBR10–25%Individual
TIGERTAIL INVESTMENT COMPANY LIMITED PARTNERSHIP ControlMEMBER25–50%Domestic Entity
WIMMER, ANGELA, MORGAN ControlPRESIDENT/PRINCIPALLess than 5%Individual
OAKTHORPE PARTNERS LLCMEMBER10–25%Domestic Entity

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 21 →

Top Trims

Show all 5 →

New Positions

  • No new positions this quarter.
Show all 0 →

Exited Positions

Show all 2 →

SOUTHERNSUN ASSET MANAGEMENT, LLC 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 Extreme Networks EXTR 30226D106 $54.6M 7.34% 1,685,450 SH
2 Louisiana-Pacific Corp LPX 546347105 $45.4M 6.12% 577,698 SH
3 Boot Barn Holdings Inc BOOT 099406100 $44.1M 5.94% 268,599 SH
4 Murphy USA Inc. MUSA 626755102 $43.1M 5.80% 79,962 SH
5 Crane NXT CXT 224441105 $42.4M 5.71% 829,182 SH
6 Darling Ingredients Inc. DAR 237266101 $41.7M 5.61% 763,305 SH
7 Live Oak Bancshares Inc LOB 53803X105 $38.2M 5.14% 934,751 SH
8 AGCO Corp. AGCO 001084102 $36.6M 4.92% 305,473 SH
9 US Physical Therapy Inc USPH 90337L108 $36.2M 4.88% 527,765 SH
10 Dorman Products Inc DORM 258278100 $35.9M 4.84% 263,383 SH
11 MSA Safety Inc MSA 553498106 $34.9M 4.69% 199,654 SH
12 Armstrong World Industries Inc AWI 04247X102 $32.2M 4.34% 200,875 SH
13 Enerpac Tool Group EPAC 292765104 $30.5M 4.10% 850,182 SH
14 The Brink's Co. BCO 109696104 $30.3M 4.08% 320,542 SH
15 CSW Industrials CSW 126402106 $26.4M 3.55% 94,698 SH
16 The Boston Beer Co Inc SAM 100557107 $23.3M 3.14% 131,877 SH
17 Modine Manufacturing Co MOD 607828100 $20.5M 2.75% 76,603 SH
18 Ingevity Corp NGVT 45688C107 $18.2M 2.46% 244,260 SH
19 Thor Industries Inc. THO 885160101 $18.0M 2.42% 238,971 SH
20 Kadant Inc KAI 48282T104 $15.3M 2.06% 48,681 SH
21 Advanced Energy Industries Inc AEIS 007973100 $14.4M 1.94% 38,683 SH
22 Generac Holdings Inc GNRC 368736104 $11.8M 1.59% 40,377 SH
23 APi Group APG 00187Y100 $10.4M 1.40% 244,797 SH
24 Valmont Industries Inc VMI 920253101 $7.9M 1.06% 13,601 SH
25 Watsco Inc WSO 942622200 $7.4M 1.00% 17,853 SH
26 Oshkosh Corp OSK 688239201 $6.7M 0.90% 43,332 SH
27 Broadridge Financial Solutions BR 11133T103 $5.9M 0.80% 43,396 SH
28 SEI Investments Co SEIC 784117103 $5.6M 0.75% 63,671 SH
29 Floor & Decor Holdings FND 339750101 $5.0M 0.67% 83,711 SH
Filing History
Period Filed AUM Holdings Accession
2026-06-30 2026-08-14 $742.8M 29 0001213900-26-089539
2026-03-31 2026-05-13 $689.9M 31 0001213900-26-055668
2025-12-31 2026-02-13 $716.4M 32 0001213900-26-015916
2025-09-30 2025-11-14 $771.8M 31 0001213900-25-110468
Filer Information
Address
240 MADISON AVENUE
SUITE 800
MEMPHIS, TN 38103
Phone
(901) 341-2700
Filing Manager
SOUTHERNSUN ASSET MANAGEMENT, LLC
Memphis, TN
Signatory
Daniel Gafford
Senior Operations Associate