Comparable stake leader
Red Oak Partners, LLC
SEC ownership of DATA I/O CORP
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0000351998.
Disclosed value leader
Red Oak Partners, LLC
Comparable rows
4/50
Latest evidence
20 Oct 2026
- Public ticker
- DAIO on Nasdaq
- Parsed ownership sources
-
13D/G, 3/4/5, and 13F
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
Red Oak Partners, LLC
Ranking: Comparable ownership first, then disclosed value
- Comparable ownership rows
-
4 of 50
Meaning: Rows with safely comparable ownership %
- Latest 13D/G holder
-
Red Oak Partners, LLC
Source: Latest parsed Schedule 13D/G stake
- Latest parsed ownership date
-
20 Oct 2026
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0000351998
- Issuer location
- Redmond, WA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
3 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of DATA I/O CORP (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
Red Oak Partners, LLC
Disclosed value leader
Red Oak Partners, LLC
Comparable rows
4/50
Latest evidence
20 Oct 2026
13D/G
3/4/5
13F
Lead comparable stake: 11%
46 rows are not safely comparable across share classes.
13D/G row: Red Oak Partners, LLC
Showing 1-8 of 50 holder rows.
Quick read
Red Oak Partners, LLC leads the comparable SEC ownership view at 11%.
4 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens Red Oak Partners, LLC's linked filing trail.
Comparable ownership
Top 4
Red Oak Partners, LLC
11%
Laurence W. Lytton
9.9%
Philotimo Fund, LP
9.1%
RENAISSANCE TECHNOLOGIES LLC
4.7%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Red Oak Partners, LLC |
13D/G
3/4/5
10%+ Owner
|
11%
Reported 13D/G
· 20 Oct 2026
|
$4,373,130
1,492,536 shares
|
$0 | 20 Oct 2026 |
| Laurence W. Lytton |
13D/G
LYTTON LAURENCE W
|
9.9%
Reported 13D/G
· 17 Jun 2026
|
$2,832,930
1,026,424 shares
|
$0 | 17 Jun 2026 |
| Philotimo Fund, LP |
13D/G
Kanen David
|
9.1%
Reported 13D/G
· 22 May 2025
|
$1,939,063
839,421 shares
|
$0 | 22 May 2025 |
| RENAISSANCE TECHNOLOGIES LLC |
13F
13D/G
Company
|
4.7%
Reported 13D/G
· 31 Dec 2025
|
$1,546,225
392,443 shares
|
— | 30 Jun 2026 |
| David Sandberg |
3/4/5
10%+ Owner
|
—
denominator unverified
|
$999,996
373,133 shares
|
+$999,996 | 20 Oct 2026 |
| Red Oak Fund, LP |
3/4/5
10%+ Owner
|
—
denominator unverified
|
$999,996
373,133 shares
|
+$999,996 | 20 Oct 2026 |
| Red Oak Long Fund, LP |
3/4/5
10%+ Owner
|
—
denominator unverified
|
$999,996
373,133 shares
|
+$999,996 | 20 Oct 2026 |
| Kanen Wealth Management LLC |
13F
Company
|
—
denominator unverified
|
$3,287,675
839,421 shares
|
— | 30 Jun 2026 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Net insider flow leans to buying over the last 12 months. Net value: +$3,999,986.
Buys
$3,999,986
Insiders: 4
Sells
$0
Insiders: 0
Net
+$3,999,986
Shares: +1,492,532
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 1,492,532
Shares: 0
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 1,492,532 | 0 | $3,999,986 | $0 | +$3,999,986 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 0 | 0 | $0 | $0 | $0 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-18 of 18 reporting-owner rows connected to DATA I/O CORP. Open a relationship link for the CIK-to-CIK filing trail.
Rows
18
Largest Forms 3/4/5 holder
Anthony Ambrose
Net 12M change
+$4M
Full value: +$3,999,984 · USD · 12-month changeLatest report
20 Oct 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Anthony Ambrose | President, Director | $1,351,908 | Mixed | 01 Jun 2024 | ||
| David Sandberg | 10%+ Owner | $999,996 | +$999,996 | +100% | Filing P/S | 20 Oct 2026 |
| Red Oak Partners, LLC | 10%+ Owner | $999,996 | +$999,996 | +100% | Filing P/S | 20 Oct 2026 |
| Red Oak Fund, LP | 10%+ Owner | $999,996 | +$999,996 | +100% | Filing P/S | 20 Oct 2026 |
| Red Oak Long Fund, LP | 10%+ Owner | $999,996 | +$999,996 | +100% | Filing P/S | 20 Oct 2026 |
| Joel S. Hatlen | Vice President CFO COO | $774,818 | Mixed | 01 Jun 2023 | ||
| Rajeev Gulati | Vice President CTO | $481,864 | Mixed | 01 Jun 2024 | ||
| Michael R. Tidwell | VP Mktg & Corp Bus Dev | $424,111 | Mixed | 01 Jun 2024 | ||
| Charles Joesph DiBona | Vice President & CFO | $353,240 | Mixed | 01 Sep 2026 | ||
| Mark J. Gallenberger | Director | $302,364 | Mixed | 20 May 2021 | ||
| Douglas Wells Brown | Director | $252,362 | Mixed | 15 May 2025 | ||
| Gerald Yat Ng | Vice President CFO | $246,053 | Mixed | 03 Jul 2024 | ||
| Sally A. Washlow | Director | $224,944 | Mixed | 08 Jul 2026 | ||
| Edward J. Smith | Director | $200,818 | Mixed | 08 Jul 2026 | ||
| Wentworth William O | President, Director | $147,195 | Mixed | 03 Dec 2025 | ||
| Garrett Riley Larson | Director | $118,484 | Mixed | 08 Jul 2026 | ||
| Cheemin Bo-Linn | Director | $66,994 | Mixed | 19 May 2022 | ||
| Steven M. Waszak | Director | $61,251 | Mixed | 08 Jul 2026 |
Recent insider transactions for DATA I/O CORP
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Red Oak Partners, LLC | DAIO | Common Stock | Purchase | $348,933 | $2.68 | 130,199 | 130,199 | 20 Oct 2026 | By The Red Oak Long Fund, LP directly | |
| Red Oak Partners, LLC | DAIO | Common Stock | Purchase | $348,933 | $2.68 | 130,199 | 130,199 | 20 Oct 2026 | By The Red Oak Long Fund, LP directly | |
| Red Oak Partners, LLC | DAIO | Common Stock | Purchase | $348,933 | $2.68 | 130,199 | 130,199 | 20 Oct 2026 | By The Red Oak Long Fund, LP directly | |
| Red Oak Partners, LLC | DAIO | Common Stock | Purchase | $348,933 | $2.68 | 130,199 | 130,199 | 20 Oct 2026 | By The Red Oak Long Fund, LP directly | |
| Red Oak Partners, LLC | DAIO | Common Stock | Purchase | $651,063 | $2.68 | 242,934 | 242,934 | 20 Oct 2026 | By The Red Oak Fund, LP directly | |
| Red Oak Partners, LLC | DAIO | Common Stock | Purchase | $651,063 | $2.68 | 242,934 | 242,934 | 20 Oct 2026 | By The Red Oak Fund, LP directly | |
| Red Oak Partners, LLC | DAIO | Common Stock | Purchase | $651,063 | $2.68 | 242,934 | 242,934 | 20 Oct 2026 | By The Red Oak Fund, LP directly | |
| Red Oak Partners, LLC | DAIO | Common Stock | Purchase | $651,063 | $2.68 | 242,934 | 242,934 | 20 Oct 2026 | By The Red Oak Fund, LP directly | |
| Red Oak Partners, LLC | DAIO | 5% Convertible Debenture | Purchase | 0 | $1,046,808 | 20 Oct 2026 | By The Red Oak Long Fund, LP directly | |||
| Red Oak Partners, LLC | DAIO | 5% Convertible Debenture | Purchase | 0 | $1,046,808 | 20 Oct 2026 | By The Red Oak Long Fund, LP directly | |||
| Red Oak Partners, LLC | DAIO | 5% Convertible Debenture | Purchase | 0 | $1,046,808 | 20 Oct 2026 | By The Red Oak Long Fund, LP directly | |||
| Red Oak Partners, LLC | DAIO | 5% Convertible Debenture | Purchase | 0 | $1,046,808 | 20 Oct 2026 | By The Red Oak Long Fund, LP directly | |||
| Red Oak Partners, LLC | DAIO | 5% Convertible Debenture | Purchase | 0 | $1,953,192 | 20 Oct 2026 | By The Red Oak Fund, LP directly | |||
| Red Oak Partners, LLC | DAIO | 5% Convertible Debenture | Purchase | 0 | $1,953,192 | 20 Oct 2026 | By The Red Oak Fund, LP directly | |||
| Red Oak Partners, LLC | DAIO | 5% Convertible Debenture | Purchase | 0 | $1,953,192 | 20 Oct 2026 | By The Red Oak Fund, LP directly | |||
| Red Oak Partners, LLC | DAIO | 5% Convertible Debenture | Purchase | 0 | $1,953,192 | 20 Oct 2026 | By The Red Oak Fund, LP directly | |||
| Charles Joesph DiBona | DAIO | Common Stock | Tax liability | -10.4% | -10,345 | 89,655 | 01 Sep 2026 | Direct | ||
| Garrett Riley Larson | DAIO | Common Stock | Award | 53.2% | 16,260 | 46,832 | 08 Jul 2026 | Direct | ||
| Edward J. Smith | DAIO | Common Stock | Award | 25.8% | 16,260 | 79,375 | 08 Jul 2026 | Direct | ||
| Sally A. Washlow | DAIO | Common Stock | Award | 22.4% | 16,260 | 88,911 | 08 Jul 2026 | Direct | ||
| Steven M. Waszak | DAIO | Common Stock | Award | 204.5% | 16,260 | 24,210 | 08 Jul 2026 | Direct | ||
| Wentworth William O | DAIO | Common Stock | Award | 2.08% | 1,100 | 53,972 | 03 Dec 2025 | Direct | ||
| Steven M. Waszak | DAIO | Common Stock | Award | 7,950 | 7,950 | 03 Dec 2025 | Direct | |||
| Wentworth William O | DAIO | Common Stock | Award | 16.4% | 7,455 | 52,872 | 02 Dec 2025 | Direct |
* marks a reported price that did not pass the local price check.