Q3 2026 13F · SEC CIK 1313559

Yorktown Management & Research Co Inc

Mutual fund managerFiled 2026-10-28 for Q3 2026. Open the filing ↗ · All SEC filings ↗

Reported 13F value: $149.7M
Reported positions: 252
Top holdings a year, 3 yrs: +14.2%
Assets under management: $677.1M

Yorktown Management & Research Co Inc is a mutual fund manager that reported 252 positions worth $149.7M in its Q3 2026 13F, filed 2026-10-28. Its largest holdings were Comfort Sys USA Inc (FIX, 3.3%), Ies Holdings Inc (IESC, 2.4%), Guardant Health Inc (GH, 1.5%). A portfolio copying its top holdings returned 14.2% a year over the last 3 years, against 20.4% for the S&P 500.

Yorktown Management & Research Co Inc holdings largest 50 of 252 positions.

Weights are shares of the filer's total reported 13F value, compared with Q2 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.

Yorktown Management & Research Co Inc 13F holdings
Stock	% of 13F value	Q2 2026	Shares	Share change	Reported value
FIXComfort Sys USA Inc	3.3%	3.6%	2,960	+0.0%	$4.9M
IESCIes Holdings Inc	2.4%	2.5%	11,020	+100.0%	$3.5M
GHGuardant Health Inc	1.5%	1.1%	12,500	+0.0%	$2.2M
ANETArista Networks Inc	1.3%	1.0%	9,800	+0.0%	$2.0M
KLACKla Corp	1.2%	1.6%	8,900	+0.0%	$1.7M
ICVTIshares Tr	1.1%	1.5%	15,000	-25.0%	$1.7M
CECOCeco Environmental Corp	1.1%	1.0%	24,309	+41.3%	$1.7M
WCCWESCO International, Inc.	1.1%	1.0%	4,550	+0.0%	$1.6M
VWOBVanguard Whitehall Fds	1.1%	1.2%	25,000	-16.7%	$1.6M
SNEXStonex Group Inc	1.0%	1.1%	23,625	+50.0%	$1.5M
CWBSpdr Series Trust	1.0%	1.3%	15,000	-25.0%	$1.5M
LQDIshares Tr	1.0%	1.0%	14,000	-6.7%	$1.4M
FNFabrinet	0.9%	1.1%	3,150	+0.0%	$1.3M
SMTCSemtech Corp	0.8%	0.7%	6,850	+0.0%	$1.2M
MLIMueller Industries, Inc.	0.8%	0.9%	19,100	+54.0%	$1.2M
BEBloom Energy Corp	0.8%	0.8%	4,150	+0.0%	$1.1M
XMTRXometry, Inc.	0.8%	0.7%	11,050	+0.0%	$1.1M
MEDPMedpace Hldgs Inc	0.8%	0.6%	1,800	+0.0%	$1.1M
DDOGDatadog Inc	0.7%	0.6%	4,000	+0.0%	$1.1M
CAMTCamtek Ltd	0.7%	0.7%	7,050	+0.0%	$1.1M
LITELumentum Hldgs Inc	0.7%	0.6%	1,125	+0.0%	$1.1M
ACMRACM Research, Inc.	0.7%	1.0%	13,300	+0.0%	$1.1M
IBKRInteractive Brokers Group in	0.7%	0.7%	12,400	+0.0%	$1.1M
FCFSFirstcash Holdings Inc	0.7%	0.7%	4,950	+0.0%	$1.0M
DGIIDigi International, Inc.	0.7%	0.6%	13,700	+0.0%	$1.0M
RJFRaymond James Finl Inc	0.7%	0.6%	6,450	+0.0%	$1.0M
NVMINova Ltd	0.7%	1.1%	2,640	-18.0%	$1.0M
LFSTLifestance Health Group Inc	0.7%	0.5%	83,600	+0.0%	$1.0M
TWSTTwist Bioscience Corp	0.7%	—	5,100	—	$986K
ROLLRbc Bearings Incorporated	0.7%	0.8%	1,970	+0.0%	$983K
RNGRingcentral Inc	0.7%	—	13,050	—	$975K
FTAIFtai Aviation Ltd	0.6%	1.0%	5,800	+0.0%	$969K
AXAxos Financial Inc	0.6%	—	11,150	—	$965K
PENPenumbra, Inc.	0.6%	0.6%	3,000	+0.0%	$955K
UUnity Software Inc Com	0.6%	—	22,550	—	$923K
INSMInsmed Inc	0.6%	—	7,925	—	$905K
WWDWoodward, Inc.	0.6%	0.7%	2,750	+0.0%	$904K
AXSMAxsome Therapeutics, Inc.	0.6%	0.7%	4,850	+0.0%	$894K
CLSCelestica Inc	0.6%	0.5%	2,450	+0.0%	$886K
FTNTFortinet Inc	0.6%	—	4,950	—	$885K
MPWRMonolithic Pwr Sys Inc	0.6%	0.6%	650	+0.0%	$876K
LPLALpl Finl Hldgs Inc	0.6%	—	2,850	—	$872K
HALOHalozyme Therapeutics Inc	0.6%	—	7,850	—	$867K
HASIHa Sustainable Infra Cap Inc	0.6%	0.6%	23,550	+0.0%	$844K
PANWPalo Alto Networks Inc	0.6%	—	2,090	—	$830K
CUBICustomers Bancorp, Inc.	0.6%	—	11,200	—	$829K
IBPInstalled Building Products, Inc.	0.6%	0.6%	4,300	+0.0%	$825K
GFIGold Fields Ltd.	0.5%	—	22,750	—	$822K
IONQIonQ, Inc.	0.5%	0.6%	18,700	+0.0%	$820K
GRALGRAIL, Inc.	0.5%	—	5,750	—	$806K

What Yorktown Management & Research Co Inc bought and sold in Q3 2026, against Q2 2026.

New positions

Q2 2026's filing was too long to tell new positions apart.

Added to

IESC Ies Holdings Inc+100.0% shares
MLI Mueller Industries, Inc.+54.0% shares
SNEX Stonex Group Inc+50.0% shares
CECO Ceco Environmental Corp+41.3% shares

Reduced

ICVT Ishares Tr-25.0% shares
CWB Spdr Series Trust-25.0% shares
NVMI Nova Ltd-18.0% shares
VWOB Vanguard Whitehall Fds-16.7% shares
LQD Ishares Tr-6.7% shares

Left the top 50

Share counts compared with the Q2 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: +24.4% /yr; S&P 500 +20.1%
3 years: +14.2% /yr; S&P 500 +20.4%
5 years: +5.3% /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
Q3 2026	$149.7M	252
Q2 2026	$163.3M	249
Q1 2026	$119.5M	214
Q4 2025	$125.1M	219
Q3 2025	$125.4M	206
Q2 2025	$104.8M	208
Q1 2025	$92.0M	206
Q4 2024	$104.0M	204
Q3 2024	$97.6M	194
Q2 2024	$93.1M	189
Q1 2024	$105.1M	217
Q4 2023	$95.8M	200

Questions about Yorktown Management & Research Co Inc's portfolio

What stocks does Yorktown Management & Research Co Inc own?

Yorktown Management & Research Co Inc's latest 13F, for Q3 2026 and filed Oct 28, 2026, lists 252 positions worth $149.7M. The largest are Comfort Sys USA Inc (FIX) at 3.3%, Ies Holdings Inc (IESC) at 2.4%, Guardant Health Inc (GH) at 1.5%, Arista Networks Inc (ANET) at 1.3% and Kla Corp (KLAC) at 1.2%.

What did Yorktown Management & Research Co Inc buy last quarter?

In Q3 2026, Yorktown Management & Research Co Inc added Ies Holdings Inc (IESC) (+100.0% shares), Mueller Industries, Inc. (MLI) (+54.0% shares) and Stonex Group Inc (SNEX) (+50.0% shares), compared with its Q2 2026 filing.

What did Yorktown Management & Research Co Inc sell last quarter?

In Q3 2026, Yorktown Management & Research Co Inc cut from its top 50 Dycom Inds Inc (DY), cut from its top 50 Applied Digital Corp (APLD), cut from its top 50 Modine Manufacturing Co (MOD), cut from its top 50 Curtiss Wright Corp (CW), cut from its top 50 Axon Enterprise Inc (AXON), Ishares Tr (ICVT) (-25.0% shares), Spdr Series Trust (CWB) (-25.0% shares) and Nova Ltd (NVMI) (-18.0% shares), compared with its Q2 2026 filing.

How has Yorktown Management & Research Co Inc's portfolio performed?

A portfolio copying Yorktown Management & Research Co Inc's 20 largest 13F holdings each quarter, from the day each filing was public, returned +14.2% a year over the last 3 years, against +20.4% for the S&P 500. Over 1 year: +24.4% against +20.1%. Over 5 years: +5.3% a year against +11.6%.

When is Yorktown Management & Research Co Inc's next 13F filing due?

13F filings are due 45 days after each quarter ends. Yorktown Management & Research Co Inc's filing for the quarter ending Dec 31, 2026 is due by Feb 14, 2027; this page updates the day after it is published.

How much money does Yorktown Management & Research Co Inc manage?

Yorktown Management & Research Co Inc reported $677.1M of regulatory assets under management on its latest SEC Form ADV. Its 13F, which covers only US-listed stocks and options, totals $149.7M.