Mirion Technologies, Inc.
Mirion Technologies, Inc. (MIR) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · MIR · as of Sep 30, 2025
Ownership Breakdown
362
Institutional Holders
▲ 39 vs Q2
$5.93B
Total Inst. Value
▲ $1.47B vs Q2
244.66M
Shares Outstanding
freeFloat 92.11%
255.86M
13F Shares Held
▲ 47.67M 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
MIR largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
BLACKROCK, INC. measuring & controlling devices, nec | 36.43M | 16.17% | 16.17% | $847.37B | Nov 12, 2025 | ▲ 19.42M |
VANGUARD GROUP INC measuring & controlling devices, nec | 30.42M | 13.50% | 13.50% | $707.53B | Nov 7, 2025 | ▲ 6.65M |
T. ROWE PRICE INVESTMENT MANAGEMENT, INC. measuring & controlling devices, nec | 21.57M | 9.57% | 9.57% | $501.64B | Nov 14, 2025 | ▲ 609.1K |
TUDOR INVESTMENT CORP ET AL measuring & controlling devices, nec | 17.50M | 7.77% | 7.77% | $18.81B | Nov 14, 2025 | ▲ 17.50M |
FMR LLC measuring & controlling devices, nec | 9.08M | 4.03% | 4.03% | $211.16B | Nov 13, 2025 | ▲ 8.13M |
STATE STREET CORP measuring & controlling devices, nec | 8.82M | 3.91% | 3.91% | $205.07B | Nov 14, 2025 | ▲ 3.72M |
COOPERMAN LEON G measuring & controlling devices, nec | 8.38M | 3.72% | 3.72% | $195.00B | Nov 14, 2025 | ▲ 1.26M |
JANUS HENDERSON GROUP PLC measuring & controlling devices, nec | 7.66M | 3.40% | 3.40% | $178.22B | Nov 14, 2025 | ▼ 326.5K |
DIMENSIONAL FUND ADVISORS LP measuring & controlling devices, nec | 6.21M | 2.75% | 2.75% | $144.36B | Nov 12, 2025 | ▼ 740.4K |
GEODE CAPITAL MANAGEMENT, LLC measuring & controlling devices, nec | 5.63M | 2.50% | 2.50% | $130.95B | Nov 12, 2025 | ▲ 889.7K |
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
30
Increased
+76.71M shares3
New Positions
first time holders17
Decreased
−12.21M shares0
Sold Out
fully exitedNet shares change (top 50)
+64.50M
+76.71M / −12.21M
Net new holders
+16
3 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
MIR insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
7
Buy transactions
7
Sell transactions
1.00
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 |
|---|---|---|---|---|---|---|---|
Kingsley Lawrence D director | May 13, 2026 | Award | 7,383 | — | — | 71.4K | Form 4 ↗ |
Bockhorst Kenneth director | May 13, 2026 | Award | 7,383 | — | — | 77.3K | Form 4 ↗ |
CASCELLA ROBERT director | May 13, 2026 | Award | 7,383 | — | — | 60.8K | Form 4 ↗ |
Etzel Steven W. director | May 13, 2026 | Award | 7,383 | — | — | 87.4K | Form 4 ↗ |
KUO JOHN W director | May 13, 2026 | Award | 7,383 | — | — | 80.1K | Form 4 ↗ |
Markopoulos Jody director | May 13, 2026 | Award | 7,383 | — | — | 81.5K | Form 4 ↗ |
Rege Sheila director | May 13, 2026 | Award | 7,383 | — | — | 49.9K | Form 4 ↗ |
Moore Christopher A. Chief Accounting Officer (PAO) | May 7, 2026 | Sale | 8,400 | $19.64 | $165.0K | 22.2K | Form 4 ↗ |
Logan Thomas D Chief Executive Officer | May 6, 2026 | Gift | 311,851 | — | — | 52.2K | Form 4 ↗ |
Ulrich Alison Chief Human Resources Officer | Apr 1, 2026 | Tax Withhold | 2,053 | $18.59 | $38.2K | 36.2K | 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
Mirion Technologies, Inc. (MIR) is primarily owned by institutional investors, who hold approximately 100.0% of total shares outstanding. Company insiders own approximately 7.89%, while retail and public investors account for the remaining 0.00%.
The largest institutional shareholder of Mirion Technologies, Inc. is BLACKROCK, INC., holding approximately 36.43 million shares — equal to 16.17% of outstanding shares — as of September 30, 2025.
A total of 362 institutional investors currently hold MIR stock, with a combined institutional value of approximately $5.93 billion as of the most recent 13F filing period.
Frequently asked questions
MIR ownershipMirion Technologies, Inc. (MIR) is primarily owned by institutional investors, who hold approximately 100.0% of shares. The largest shareholder is BLACKROCK, INC. with a 16.17% stake. Company insiders hold 7.89%. Data sourced from SEC Form 13F as of September 30, 2025.