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OAK ASSOCIATES LTD /OH/ — 13F Holdings & Portfolio

CIK 836372 · latest 13F-HR filed 2026-08-14

Backtest portfolio

OAK ASSOCIATES LTD /OH/ manages $1.79B in 13F-reported U.S. long-equity assets across 139 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are KLAC (10.00%), AMZN (6.85%), GOOG (6.61%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 8 new positions and exited 9; 73 existing positions rose in reported value and 31 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
$1.79B

Long-equity book

Holdings
139

Distinct positions

Period
2026-06-30

Filed 2026-08-14

Q/Q Activity
+8 / −9 / ↑73 / ↓31

vs 2026-03-31

Portfolio charts

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

Portfolio map

Q2 26
KLAC10.0% · +866%AMZN6.9% · -0%GOOG6.6% · -5%CSCO6.0% · -1%AVGO4.5% · -10%NVDA3.4% · -0%AMD3.3% · -1%V3.0% · -2%META2.9% · -2%MSFT2.9% · -0%GOOGL2.9% · -6%NXPI2.7% · +1%AMGN2.2% · -1%SCHW2.2% · -1%JPM1.9% · -1%AAPL1.8% · 0%APH1.7% · +4%SNPS1.6% · 0%QCOM1.6% · -0%NTAP1.5% · -13%NVS1.4% · -1%CB1.3% · -1%ADBE1.3% · -9%LOW1.3% · -1%ASML1.2% · newLRCX1.1% · 0%ROK1.0% · -1%LH1.0% · -1%MA0.9% · -1%LMT0.9% · 0%AKAM0.9% · 0%CI0.7% · -1%NFLX0.7% · 0%ALC0.6% · -1%STT0.6% · -2%GILD0.6% · -1%CDNS0.5% · -2%BNY0.5% · newMCK0.5% · 0%AIZ0.5% · 0%KLIC0.5% · 0%AIT0.5% · 0%CRM0.4% · -1%CRUS0.4% · -0%ORCL0.4% · 0%BMY0.4% · -2%SIMO0.4% · -17%REGN0.4% · 0%WDAY0.3% · 0%EOG0.3% · -1%ABNB0.3% · -2%EXPE0.3% · 0%COHU0.3% · 0%DOX0.3% · -3%SLB0.3% · -1%DVN0.3% · +56%CRWD0.3% · -14%CAH0.3% · 0%INTU0.3% · 0%LNTH0.2% · 0%

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 = 49.4%

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

Firm Profile & Key People

As of the firm’s regulatory filing dated Mar 6, 2026.

Assets Under Management
$1.78B
Discretionary
$1.77B
Employees
8
Accounts
56
Address
3800 EMBASSY PARKWAY
SUITE 31O
AKRON, OH 44333
Phone
(330) 668-1234
Website
Name Title / Status Ownership Type
BALLINGER, MARGARET, LYNN ControlPRESIDENT / MANAGING MEMBER / CHIEF OPERATING OFFICER / CHIEF COMPLIANCE OFFICER
since Jan 1996
25–50%Individual
STIMPSON, ROBERT, DONALD ControlMANAGING MEMBER / CHIEF INVESTMENT OFFICER
since Jan 2019
50–75%Individual
Ownership & leadership changes · 9 filings with changes since Mar 30, 2012

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.

Oct 22, 2024 filing
  • No longer listedOELSCHLAGER, JAMES, DRAVO · CO-CHIEF INVESTMENT OFFICER · Less than 5% · control person · listed since Jan 1996
  • ChangedSTIMPSON, ROBERT, DONALD · title MANAGING MEMBER / CO-CHIEF INVESTMENT OFFICER → MANAGING MEMBER / CHIEF INVESTMENT OFFICER
Jan 19, 2024 filing
  • No longer listedZOLLARS, CAROL, LYNN · MANAGING MEMBER / CHIEF FINANCIAL OFFICER · 10–25% · control person · listed since Jan 2019
  • ChangedSTIMPSON, ROBERT, DONALD · ownership 25–50% → 50–75%
Mar 23, 2022 filing
  • ChangedBALLINGER, MARGARET, LYNN · title MANAGING MEMBER / CHIEF OPERATING OFFICER / CHIEF COMPLIANCE OFFICER → PRESIDENT / MANAGING MEMBER / CHIEF OPERATING OFFICER / CHIEF COMPLIANCE OFFICER
Jan 14, 2020 filing
  • ChangedBALLINGER, MARGARET, LYNN · title CHIEF COMPLIANCE OFFICER / CHIEF OPERATING OFFICER → MANAGING MEMBER / CHIEF OPERATING OFFICER / CHIEF COMPLIANCE OFFICER; ownership Less than 5% → 25–50%
  • ChangedOELSCHLAGER, JAMES, DRAVO · title MANAGING MEMBER/PORTFOLIO MANAGER → CO-CHIEF INVESTMENT OFFICER; ownership 75% or more → Less than 5%
  • ChangedSTIMPSON, ROBERT, DONALD · title CO-CHIEF INVESTMENT OFFICER → MANAGING MEMBER / CO-CHIEF INVESTMENT OFFICER; ownership Less than 5% → 25–50%
  • ChangedZOLLARS, CAROL, LYNN · title CHIEF FINANCIAL OFFICER → MANAGING MEMBER / CHIEF FINANCIAL OFFICER; ownership Less than 5% → 10–25%
Mar 29, 2019 filing
  • AddedSTIMPSON, ROBERT, DONALD · CO-CHIEF INVESTMENT OFFICER · Less than 5% · control person
  • AddedZOLLARS, CAROL, LYNN · CHIEF FINANCIAL OFFICER · Less than 5% · control person
Mar 26, 2015 filing
  • ChangedBALLINGER, MARGARET, LYNN · title CHIEF COMPLIANCE OFFICER / DIRECTOR OF OPERATIONS → CHIEF COMPLIANCE OFFICER / CHIEF OPERATING OFFICER
Jan 21, 2015 filing
  • No longer listedNOLL, SANDRA, HELEN · CHIEF COMPLIANCE OFFICER · Less than 5% · control person · listed since Nov 1994
  • ChangedBALLINGER, MARGARET, LYNN · title DIRECTOR OF OPERATIONS → CHIEF COMPLIANCE OFFICER / DIRECTOR OF OPERATIONS; now a control person
Mar 31, 2014 filing
  • ChangedBALLINGER, MARGARET, LYNN · title ASSISTANT PORTFOLIO MANAGER → DIRECTOR OF OPERATIONS
Mar 26, 2013 filing
  • No longer listedBARTON, DONNA, LOU · ASSISTANT PORTFOLIO MANAGER/TRADER · Less than 5% · listed since Jan 1996
Mar 30, 2012 filing (earliest on record)
  • ListedBALLINGER, MARGARET, LYNN · ASSISTANT PORTFOLIO MANAGER · Less than 5%
  • ListedBARTON, DONNA, LOU · ASSISTANT PORTFOLIO MANAGER/TRADER · Less than 5%
  • ListedNOLL, SANDRA, HELEN · CHIEF COMPLIANCE OFFICER · Less than 5% · control person
  • ListedOELSCHLAGER, JAMES, DRAVO · MANAGING MEMBER/PORTFOLIO MANAGER · 75% or more · 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.

OAK ASSOCIATES LTD /OH/ 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 KLA Corporation KLAC 482480100 $178.7M 10.00% 592,265 SH
2 Amazon.com Inc. AMZN 023135106 $122.5M 6.85% 513,856 SH
3 Alphabet Inc. Class C GOOG 02079K107 $118.1M 6.61% 334,320 SH
4 Cisco Systems Inc. CSCO 17275R102 $107.3M 6.00% 913,345 SH
5 Broadcom Limited AVGO 11135F101 $80.5M 4.50% 213,136 SH
6 NVIDIA Corp NVDA 67066G104 $60.6M 3.39% 302,749 SH
7 Advanced Micro Devices AMD 007903107 $58.8M 3.29% 101,266 SH
8 VISA Inc. V 92826C839 $53.7M 3.00% 156,397 SH
9 Meta Platforms, Inc. META 30303M102 $51.2M 2.87% 90,960 SH
10 Microsoft Corporation MSFT 594918104 $51.1M 2.86% 136,992 SH
11 Alphabet Inc. Class A GOOGL 02079K305 $51.0M 2.85% 142,621 SH
12 NXP Semiconductors NV NXPI N6596X109 $48.4M 2.71% 172,172 SH
13 Amgen Inc. AMGN 031162100 $39.7M 2.22% 109,731 SH
14 Charles Schwab Corp SCHW 808513105 $39.2M 2.19% 424,880 SH
15 JPMorgan Chase & Co JPM 46625H100 $34.8M 1.95% 106,443 SH
16 Apple Inc. AAPL 037833100 $32.7M 1.83% 112,894 SH
17 Amphenol Corp. APH 032095101 $31.2M 1.74% 176,732 SH
18 Synopsys Inc. SNPS 871607107 $28.6M 1.60% 64,174 SH
19 Qualcomm Inc. QCOM 747525103 $27.9M 1.56% 151,167 SH
20 NetApp, Inc. NTAP 64110D104 $26.1M 1.46% 168,552 SH
21 Novartis AG NVS 66987V109 $24.3M 1.36% 155,362 SH
22 Chubb Limited CB H1467J104 $24.0M 1.34% 70,336 SH
23 Adobe Inc. ADBE 00724F101 $23.2M 1.30% 113,197 SH
24 Lowes Companies Inc. LOW 548661107 $23.1M 1.29% 104,557 SH
25 ASML Hldg NV NY Reg Shs ASML N07059210 $21.3M 1.19% 10,698 SH
26 Lam Research Corporation LRCX 512807306 $19.4M 1.09% 44,821 SH
27 Rockwell Automation Inc ROK 773903109 $17.9M 1.00% 36,146 SH
28 Laboratory Corp of America LH 504922105 $17.5M 0.98% 62,607 SH
29 Mastercard Inc. MA 57636Q104 $16.7M 0.94% 32,603 SH
30 Lockheed Martin Corp. LMT 539830109 $16.4M 0.92% 32,133 SH
31 Akamai Technologies Inc. AKAM 00971T101 $16.2M 0.90% 136,694 SH
32 The Cigna Group CI 125523100 $13.1M 0.73% 47,410 SH
33 Netflix Inc NFLX 64110L106 $12.5M 0.70% 175,000 SH
34 Alcon Inc ALC H01301128 $11.2M 0.63% 166,716 SH
35 State Street Corp STT 857477103 $10.6M 0.59% 62,328 SH
36 Gilead Sciences Inc. GILD 375558103 $10.2M 0.57% 80,646 SH
37 Cadence Design Systems, Inc. CDNS 127387108 $9.5M 0.53% 25,184 SH
38 Bank of New York Mellon Corp. BNY 064058100 $9.4M 0.53% 65,110 SH
39 McKesson Corp MCK 58155Q103 $8.9M 0.50% 11,814 SH
40 Assurant, Inc. AIZ 04621X108 $8.8M 0.49% 32,938 SH
41 Kulicke & Soffa Industries KLIC 501242101 $8.2M 0.46% 61,401 SH
42 Applied Industrial Tech AIT 03820C105 $8.1M 0.45% 23,979 SH
43 Salesforce, Inc CRM 79466L302 $7.7M 0.43% 48,893 SH
44 Cirrus Logic Inc. CRUS 172755100 $7.6M 0.43% 51,157 SH
45 Oracle Corporation ORCL 68389X105 $7.5M 0.42% 51,183 SH
46 Bristol-Myers Squibb Co. BMY 110122108 $7.5M 0.42% 129,790 SH
47 Silicon Motion Tech ADS SIMO 82706C108 $7.1M 0.40% 21,241 SH
48 Regeneron Pharmaceuticals REGN 75886F107 $6.6M 0.37% 10,560 SH
49 Workday, Inc. WDAY 98138H101 $6.2M 0.35% 50,954 SH
50 EOG Resources Inc EOG 26875P101 $6.0M 0.34% 46,591 SH
Filing History
Period Filed AUM Holdings Accession
2026-06-30 2026-08-14 $1.79B 139 0001193125-26-352266
2026-03-31 2026-05-14 $1.49B 140 0001193125-26-223607
2025-12-31 2026-02-12 $1.66B 131 0001193125-26-048895
2025-09-30 2025-11-12 $1.64B 130 0001193125-25-277361
Filer Information
Address
3800 EMBASSY PARKWAY
SUITE 310
AKRON, OH 44333
Phone
(330) 668-1234
Filing Manager
OAK ASSOCIATES LTD /OH/
AKRON, OH
Signatory
Robert D. Stimpson
Managing Member