ClearSign Technologies Corporation
ClearSign Technologies Corporation (CLIR) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · CLIR · as of Sep 30, 2025
Ownership Breakdown
40
Institutional Holders
▲ 4 vs Q2
$3.27M
Total Inst. Value
▲ $815,989 vs Q2
6.19M
Shares Outstanding
freeFloat 72.00%
4.23M
13F Shares Held
▼ 270,290 vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
CLIR largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
VANGUARD GROUP INC industrial instruments for measurement, display, and control | 1.28M | 2.29% | 2.29% | $985.02M | Nov 7, 2025 | ▲ 112.2K |
SIMON QUICK ADVISORS, LLC industrial instruments for measurement, display, and control | 603.1K | 1.08% | 1.08% | $465.15M | Oct 21, 2025 | — held |
GEODE CAPITAL MANAGEMENT, LLC industrial instruments for measurement, display, and control | 523.2K | 93.86% | 93.86% | $403.60M | Nov 12, 2025 | ▼ 30.4K |
CAMBRIDGE INVESTMENT RESEARCH ADVISORS, INC. industrial instruments for measurement, display, and control | 443.0K | 79.47% | 79.47% | $342.00M | Nov 12, 2025 | — held |
BLACKROCK, INC. industrial instruments for measurement, display, and control | 199.3K | 35.75% | 35.75% | $153.70M | Nov 12, 2025 | — held |
CREATIVE PLANNING industrial instruments for measurement, display, and control | 159.1K | 28.53% | 28.53% | $122.66M | Nov 14, 2025 | ▲ 17.2K |
HIGHTOWER ADVISORS, LLC industrial instruments for measurement, display, and control | 126.8K | 22.75% | 22.75% | $97.80M | Nov 7, 2025 | ▼ 2.0K |
DDD PARTNERS, LLC industrial instruments for measurement, display, and control | 115.0K | 20.63% | 20.63% | $88.69M | Nov 6, 2025 | — held |
STATE STREET CORP industrial instruments for measurement, display, and control | 89.0K | 15.96% | 15.96% | $68.63M | Nov 14, 2025 | — held |
NORTHERN TRUST CORP industrial instruments for measurement, display, and control | 75.5K | 13.54% | 13.54% | $58.20M | Nov 14, 2025 | — held |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
7
Increased
+144.5K shares6
New Positions
first time holders11
Decreased
−147.6K shares5
Sold Out
fully exitedNet shares change (top 50)
3.1K
+144.5K / −147.6K
Net new holders
-3
6 new / 5 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
CLIR insider trading · insider activity
Source: SEC Form 4
Insiders have been net buyers of shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
12
Buy transactions
8
Sell transactions
1.50
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Deller Colin James Chief Executive Officer | Feb 26, 2026 | Award | 7,001 | $5.62 | $39.3K | 35.0K | Form 4 ↗ |
Deller Colin James Chief Executive Officer | Feb 26, 2026 | Tax Withhold | 3,501 | $5.62 | $19.7K | 31.5K | Form 4 ↗ |
Silva Gil Todd director | Apr 23, 2026 | Purchase | 1,000 | $5.25 | $5.3K | 6.0K | Form 4 ↗ |
Silva Gil Todd director | Apr 23, 2026 | Purchase | 1,000 | $5.32 | $5.3K | 5.0K | Form 4 ↗ |
Basenese Lou director | Mar 31, 2026 | Award | 3,024 | $4.36 | $13.2K | 3.0K | Form 4 ↗ |
Silva Gil Todd director | Mar 31, 2026 | Award | 3,440 | — | — | 123.9K | Form 4 ↗ |
Silva Gil Todd director | Mar 31, 2026 | Award | 3,024 | $4.36 | $13.2K | 3.0K | Form 4 ↗ |
DIGIANDOMENICO ANTHONY director | Mar 31, 2026 | Award | 3,024 | $4.36 | $13.2K | 3.0K | Form 4 ↗ |
Silva Gil Todd director | Mar 17, 2026 | Purchase | 2,000 | $4.20 | $8.4K | 4.0K | Form 4 ↗ |
Silva Gil Todd director | Mar 16, 2026 | Purchase | 2,000 | $4.36 | $8.7K | 2.0K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
ClearSign Technologies Corporation (CLIR) is primarily owned by institutional investors, who hold approximately 68.4% of total shares outstanding. Company insiders own approximately 28.00%, while retail and public investors account for the remaining 3.60%.
The largest institutional shareholder of ClearSign Technologies Corporation is VANGUARD GROUP INC, holding approximately 1.28 million shares — equal to 2.29% of outstanding shares — as of September 30, 2025.
A total of 40 institutional investors currently hold CLIR stock, with a combined institutional value of approximately $3,267,120 as of the most recent 13F filing period.
Frequently asked questions
CLIR ownershipClearSign Technologies Corporation (CLIR) is primarily owned by institutional investors, who hold approximately 68.4% of shares. The largest shareholder is VANGUARD GROUP INC with a 2.29% stake. Company insiders hold 28.00%. Data sourced from SEC Form 13F as of September 30, 2025.