Q2 2026 13F · SEC CIK 1803227

Mattern Capital Management, LLC

Wealth managerFiled 2026-07-24 for Q2 2026. Open the filing ↗ · All SEC filings ↗

Reported 13F value: $856.7M
Reported positions: 166
Top holdings a year, 3 yrs: +13.4%
Assets under management: $1.1B

Mattern Capital Management, LLC is a wealth manager that reported 166 positions worth $856.7M in its Q2 2026 13F, filed 2026-07-24. Its largest holdings were Apple Inc (AAPL, 2.6%), Ww Grainger Inc (GWW, 1.9%), Microsoft Corp (MSFT, 1.8%). A portfolio copying its top holdings returned 13.4% a year over the last 3 years, against 20.4% for the S&P 500.

Mattern Capital Management, LLC holdings largest 50 of 166 positions.

Weights are shares of the filer's total reported 13F value, compared with Q1 2026. Share changes may reflect splits; weight changes also reflect price moves. A 13F shows long US-listed positions only, up to 135 days after the fact.

Mattern Capital Management, LLC 13F holdings
Stock	% of 13F value	Q1 2026	Shares	Share change	Reported value
AAPLApple Inc	2.6%	2.4%	76,362	-1.6%	$22.1M
GWWWw Grainger Inc	1.9%	1.6%	11,817	-1.6%	$16.1M
MSFTMicrosoft Corp	1.8%	1.8%	41,086	-0.6%	$15.3M
UNHUnitedhealth Group Inc	1.7%	1.3%	35,240	-9.1%	$14.6M
COSTCostco Wholesale Corporation	1.6%	1.7%	14,372	-0.3%	$13.4M
AVGOBroadcom Inc	1.6%	1.4%	35,199	-5.4%	$13.3M
CORCencora Inc	1.5%	1.6%	46,831	+11.5%	$13.3M
AFLAflac Inc	1.5%	1.5%	110,309	-0.3%	$12.9M
CSCOCisco Sys Inc	1.5%	—	106,058	—	$12.5M
LINLinde PLC	1.4%	1.4%	23,750	-1.4%	$12.3M
CBChubb Limited	1.4%	1.4%	35,965	-0.4%	$12.3M
LLYEli Lilly & Co	1.4%	1.1%	10,188	+6.2%	$12.2M
WECWec Energy Group Inc	1.4%	1.5%	103,889	-5.5%	$12.1M
LOWLowes Cos Inc	1.4%	1.5%	54,910	+5.6%	$12.1M
GDGeneral Dynamics Corp	1.4%	1.4%	33,512	+1.6%	$11.9M
TXNTexas Instrs Inc	1.4%	—	39,548	—	$11.8M
NEENextera Energy Inc	1.3%	1.5%	131,600	-1.7%	$11.6M
CMSCMS Energy Corp	1.3%	1.5%	150,896	-5.5%	$11.5M
ADPAutomatic Data Processing in	1.3%	1.2%	50,215	+1.7%	$11.2M
AWKAmerican Wtr Wks Co Inc New Com	1.3%	1.4%	84,940	-3.0%	$11.2M
TTTrane Technologies PLC	1.3%	1.2%	22,695	-4.0%	$11.1M
APHAmphenol Corp	1.3%	—	62,586	—	$11.0M
BROBrown & Brown Inc Com	1.3%	1.1%	169,855	+19.0%	$10.9M
SHWSherwin Williams Co	1.3%	1.1%	31,373	+7.2%	$10.8M
FDSFactset Resh Sys Inc	1.3%	1.2%	46,828	+0.3%	$10.8M
LHXL3harris Technologies Inc	1.2%	1.4%	36,645	+5.5%	$10.6M
HDHome Depot Inc	1.2%	1.1%	30,013	+10.1%	$10.6M
WMTWalmart Inc	1.2%	1.3%	93,445	+5.9%	$10.6M
PAYXPaychex Inc	1.2%	1.2%	107,571	+0.3%	$10.6M
ADIAnalog Devices Inc	1.2%	—	26,398	—	$10.5M
JPMJpmorgan Chase & Co	1.2%	—	31,711	—	$10.4M
ECLEcolab Inc	1.2%	1.1%	36,966	+4.1%	$10.3M
MSIMotorola Solutions Inc	1.2%	1.3%	24,690	+0.5%	$10.3M
ATOAtmos Energy Corp	1.2%	1.3%	59,371	-0.6%	$10.2M
BLKBlackrock Inc	1.2%	1.2%	10,621	+2.3%	$10.2M
AMGNAmgen Inc	1.2%	—	28,008	—	$10.1M
JNJJohnson & Johnson	1.2%	—	39,870	—	$10.1M
VVisa Inc	1.2%	—	29,508	—	$10.1M
PHParker-Hannifin Corp	1.2%	—	10,138	—	$9.9M
ABTAbbott Laboratories	1.2%	1.3%	109,046	+3.0%	$9.9M
ITWIllinois Tool Wks Inc	1.2%	1.1%	36,515	+3.0%	$9.9M
XYLXylem Inc	1.2%	1.1%	83,398	+10.2%	$9.9M
WMWaste Mgmt Inc Del	1.1%	1.2%	44,162	+4.3%	$9.8M
SPGIS&p Global Inc	1.1%	1.1%	24,125	+10.5%	$9.8M
ROPRoper Technologies Inc	1.1%	1.2%	29,027	-0.1%	$9.8M
NJRNew Jersey Res Corp	1.1%	1.2%	174,671	-3.0%	$9.8M
SYKStryker Corporation	1.1%	1.0%	31,079	+16.6%	$9.8M
PLDPrologis Inc	1.1%	1.1%	71,369	-1.5%	$9.7M
CLColgate Palmolive Co	1.1%	1.1%	104,479	+0.2%	$9.6M
CTASCintas Corp	1.1%	1.0%	55,902	+8.1%	$9.5M

What Mattern Capital Management, LLC bought and sold in Q2 2026, against Q1 2026.

New positions

Q1 2026's filing was too long to tell new positions apart.

Added to

BRO Brown & Brown Inc Com+19.0% shares
SYK Stryker Corporation+16.6% shares
COR Cencora Inc+11.5% shares
SPGI S&p Global Inc+10.5% shares
XYL Xylem Inc+10.2% shares
HD Home Depot Inc+10.1% shares
CTAS Cintas Corp+8.1% shares
SHW Sherwin Williams Co+7.2% shares

Reduced

Left the top 50

PSX Phillips 66was 1.9%
CEG Constellation Energy Corpwas 1.2%
BR Broadridge Finl Solutions inwas 1.2%
INTU Intuitwas 1.2%
ACN Accenture PLC Irelandwas 1.1%
MCD Mcdonalds Corpwas 1.1%
ICE Intercontinental Exchange Incwas 1.1%
PEP Pepsico Incwas 1.1%

Share counts compared with the Q1 2026 13F; a split also changes share counts. The latest filing lists more than 50 positions, so a position that left the top 50 may still be held.

How the holdings did against the S&P 500.

1 year: +16.4% /yr; S&P 500 +20.1%
3 years: +13.4% /yr; S&P 500 +20.4%
5 years: +7.5% /yr; S&P 500 +11.6%

A portfolio of the filer's 20 largest 13F positions, weighted by value, bought the trading day after each 13F was filed and held until the next one was: what copying this filer could have earned. 13Fs show long US-listed positions only, so this is an estimate of the stock picks, not the fund's reported returns.

Reported 13F value by quarter.

13F value by quarter
Quarter	13F value	Positions
Q2 2026	$856.7M	166
Q1 2026	$834.9M	170
Q4 2025	$846.9M	170
Q3 2025	$850.6M	172
Q2 2025	$832.4M	170
Q1 2025	$785.4M	163
Q4 2024	$767.4M	160
Q3 2024	$794.6M	156
Q2 2024	$723.8M	157
Q1 2024	$736.5M	157
Q4 2023	$687.9M	136
Q3 2023	$618.2M	135

Questions about Mattern Capital Management, LLC's portfolio

What stocks does Mattern Capital Management, LLC own?

Mattern Capital Management, LLC's latest 13F, for Q2 2026 and filed Jul 24, 2026, lists 166 positions worth $856.7M. The largest are Apple Inc (AAPL) at 2.6%, Ww Grainger Inc (GWW) at 1.9%, Microsoft Corp (MSFT) at 1.8%, Unitedhealth Group Inc (UNH) at 1.7% and Costco Wholesale Corporation (COST) at 1.6%.

What did Mattern Capital Management, LLC buy last quarter?

In Q2 2026, Mattern Capital Management, LLC added Brown & Brown Inc Com (BRO) (+19.0% shares), Stryker Corporation (SYK) (+16.6% shares) and Cencora Inc (COR) (+11.5% shares), compared with its Q1 2026 filing.

What did Mattern Capital Management, LLC sell last quarter?

In Q2 2026, Mattern Capital Management, LLC cut from its top 50 Phillips 66 (PSX), cut from its top 50 Constellation Energy Corp (CEG), cut from its top 50 Broadridge Finl Solutions in (BR), cut from its top 50 Intuit (INTU), cut from its top 50 Accenture PLC Ireland (ACN), Unitedhealth Group Inc (UNH) (-9.1% shares), Wec Energy Group Inc (WEC) (-5.5% shares) and CMS Energy Corp (CMS) (-5.5% shares), compared with its Q1 2026 filing.

How has Mattern Capital Management, LLC's portfolio performed?

A portfolio copying Mattern Capital Management, LLC's 20 largest 13F holdings each quarter, from the day each filing was public, returned +13.4% a year over the last 3 years, against +20.4% for the S&P 500. Over 1 year: +16.4% against +20.1%. Over 5 years: +7.5% a year against +11.6%.

When is Mattern Capital Management, LLC's next 13F filing due?

13F filings are due 45 days after each quarter ends. Mattern Capital Management, LLC's filing for the quarter ending Sep 30, 2026 is due by Nov 14, 2026; this page updates the day after it is published.

How much money does Mattern Capital Management, LLC manage?

Mattern Capital Management, LLC reported $1.1B of regulatory assets under management on its latest SEC Form ADV. Its 13F, which covers only US-listed stocks and options, totals $856.7M.