DATA I O CORP DAIO
COM · Common Stock · CUSIP 237690102
- SectorTechnology
- IndustryInstruments For Meas & Testing of Electricity & Elec Signals
- HeadquartersRedmond, WA
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once. Holder counts are more reliable. Shares outstanding: 10.4m as of 2026-07-31, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $3.93. Options: 2 managers hold calls ($91.8k notional), 0 hold puts (—).
Trends to Q2 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 29 |
| Q4 2022 | 31 |
| Q1 2023 | 31 |
| Q2 2023 | 30 |
| Q3 2023 | 30 |
| Q4 2023 | 31 |
| Q1 2024 | 33 |
| Q2 2024 | 33 |
| Q3 2024 | 30 |
| Q4 2024 | 30 |
| Q1 2025 | 27 |
| Q2 2025 | 27 |
| Q3 2025 | 26 |
| Q4 2025 | 27 |
| Q1 2026 | 29 |
| Q2 2026 | 35 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q3 2024 | 7 | 12 |
| Q4 2024 | 6 | 10 |
| Q1 2025 | 7 | 9 |
| Q2 2025 | 13 | 9 |
| Q3 2025 | 7 | 9 |
| Q4 2025 | 11 | 9 |
| Q1 2026 | 7 | 10 |
| Q2 2026 | 18 | 9 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2025 | $1.3k | $265.5k | 198.75 |
| Q4 2025 | $1.2m | $0 | 0.00 |
| Q1 2026 | $133.3k | $139.2k | 1.04 |
| Q2 2026 | $91.8k | $0 | 0.00 |
Biggest buyers
| CITADEL ADVISORS LLC | New | +86.9k |
| GEODE CAPITAL MANAGEMENT, LLC | Added | +28.2k |
| VANGUARD CAPITAL MANAGEMENT LLC | Added | +24.3k |
| THOMPSON DAVIS & CO., INC. | New | +23.5k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | +21.7k |
| JANE STREET GROUP, LLC | New | +17.7k |
| Kovack Advisors, Inc. | Added | +17.5k |
| XTX Topco Ltd | New | +15.3k |
| VANGUARD FIDUCIARY TRUST CO | Added | +12.8k |
| HRT FINANCIAL LP | New | +11.3k |
Biggest sellers
| ACADIAN ASSET MANAGEMENT LLC | Reduced | -15.5k |
| RENAISSANCE TECHNOLOGIES LLC | Reduced | -15.2k |
| GOLDMAN SACHS GROUP INC | Sold out | -13.8k |
| LPL Financial LLC | Reduced | -1.5k |
| Tower Research Capital LLC (TRC) | Reduced | -1.4k |
| Penbrook Management LLC | Reduced | -1.0k |
| ROYAL BANK OF CANADA | Sold out | -136 |
| BARD ASSOCIATES INC | Sold out | -100 |
| ESSEX INVESTMENT MANAGEMENT CO LLC | Reduced | -83 |
Biggest calls
| GROUP ONE TRADING LLC | Added | $53.6k13.6k shares |
| SIMPLEX TRADING, LLC | New | $38.2k9.7k shares |
Biggest puts
| None |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| Red Oak Partners, LLC 13G · passive investor new · filed 2026-10-27 | 11.2% |
| LYTTON LAURENCE W 13G · passive investor new · filed 2026-06-23 | 9.9% |
| Philotimo Fund, LP 13G · passive investor filed 2025-05-22 | 9.1% |
Fell to 5% or below in the last year: RENAISSANCE TECHNOLOGIES LLC (4.7%, 2026-02-12)
Insider purchases and sales since 1 Apr 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2024 | 0 | — | 0 | — | — |
| Q1 2025 | 0 | — | 0 | — | — |
| Q2 2025 | 2 | $62.3k | 0 | — | — |
| Q3 2025 | 0 | — | 0 | — | — |
| Q4 2025 | 0 | — | 0 | — | — |
| Q1 2026 | 0 | — | 0 | — | — |
| Q2 2026 | 0 | — | 0 | — | — |
| Q3 2026 | 0 | — | 0 | — | — |
None reported since 1 Apr 2026.
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| Kanen Wealth Management LLC 0.80% of their portfolio | 839.4k $3.3m | Unchanged |
| RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio | 392.4k $1.5m | Reduced -15.2k |
| Penbrook Management LLC 0.89% of their portfolio | 355.9k $1.4m | Reduced -1.0k |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 323.7k $1.3m | Added +24.3k |
| Kovack Advisors, Inc. 0.05% of their portfolio | 285.5k $1.1m | Added +17.5k |
| DIMENSIONAL FUND ADVISORS LP 0.00% of their portfolio | 140.7k $554.3k | Unchanged |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 115.1k $453.4k | Added +28.2k |
| ACADIAN ASSET MANAGEMENT LLC 0.00% of their portfolio | 108.6k $427.0k | Reduced -15.5k |
| CITADEL ADVISORS LLC 0.00% of their portfolio | 86.9k $342.3k | New |
| ESSEX INVESTMENT MANAGEMENT CO LLC 0.04% of their portfolio | 74.6k $293.8k | Reduced -83 |
| VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio | 58.6k $231.1k | Added +12.8k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio | 48.5k $191.3k | Added +21.7k |
| Steward Partners Investment Advisory, LLC 0.00% of their portfolio | 43.5k $171.3k | Unchanged |
| THOMPSON DAVIS & CO., INC. 0.06% of their portfolio | 23.5k $92.7k | New |
| JAMES INVESTMENT RESEARCH, INC. 0.01% of their portfolio | 22.4k $88.3k | Unchanged |
| NewEdge Advisors, LLC 0.00% of their portfolio | 22.4k $88.3k | Unchanged |
| NORTHERN TRUST CORP 0.00% of their portfolio | 21.8k $86.0k | Added +8.4k |
| LPL Financial LLC 0.00% of their portfolio | 21.0k $82.7k | Reduced -1.5k |
| JANE STREET GROUP, LLC 0.00% of their portfolio | 17.7k $69.8k | New |
| Legato Capital Management LLC 0.01% of their portfolio | 17.6k $69.1k | Unchanged |
| BlackRock, Inc. 0.00% of their portfolio | 17.0k $67.0k | Unchanged |
| STATE STREET CORP 0.00% of their portfolio | 16.2k $63.7k | Unchanged |
| XTX Topco Ltd 0.00% of their portfolio | 15.3k $60.2k | New |
| HRT FINANCIAL LP 0.00% of their portfolio | 11.3k $44.0k | New |
| CITIGROUP INC 0.00% of their portfolio | 7.2k $28.3k | New |
| GROUP ONE TRADING LLC 0.00% of their portfolio | 6.5k $25.4k | Added +6.3k |
| Vanguard Global Advisers, LLC 0.00% of their portfolio | 5.1k $20.2k | Unchanged |
| SIMPLEX TRADING, LLC 0.00% of their portfolio | 4.3k $16.9k | Added +1.5k |
| UBS Group AG 0.00% of their portfolio | 4.2k $16.6k | Added +3.3k |
| Point Nemo Capital, LLC 0.00% of their portfolio | 500 $2.0k | New |
| Tower Research Capital LLC (TRC) 0.00% of their portfolio | 314 $1.2k | Reduced -1.4k |
| BARCLAYS PLC 0.00% of their portfolio | 50 $197 | New |
| Caitong International Asset Management Co., Ltd 0.00% of their portfolio | 4 $16 | New |
| HUNTINGTON NATIONAL BANK 0.00% of their portfolio | 1 $4 | Unchanged |
| SBI Securities Co., Ltd. 0.00% of their portfolio | 1 $4 | Unchanged |