Mirion Technologies, Inc.
US ˙ NYSE

SecurityMIR / Mirion Technologies, Inc.
InstitutionCitadel Advisors Llc
ManagerKen Griffin
Latest Disclosed Ownership1,823,252 shares
Latest Disclosed Value $ 33,894,255
Citadel Advisors Llc ownership in MIR / Mirion Technologies, Inc.

On May 15, 2026 - Citadel Advisors Llc filed a 13F-HR form disclosing ownership of 1,823,252 shares of Mirion Technologies, Inc. (US:MIR) valued at $33,894,255 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 1,620,793 shares of Mirion Technologies, Inc.. This represents a change in shares of 12.49% during the quarter. The current value of the position is $33,256,116 USD.

Citadel Advisors Llc has a history of taking positions in derivatives of the underlying security (MIR) in the form of stock options. The firm currently holds call options representing 209,400 of underlying shares valued at $3,892,746 USD and put options representing 16,200 of underlying shares valued at $301,158 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MIR / Mirion Technologies, Inc. Historical Put/Call Ratio
Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 1,823,252 202,459 12.49 33,894 -10.71 0.0048
2026-02-17 2025-12-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 1,620,793 1,430,949 753.75 37,959 759.75 0.0057
2025-11-14 2025-09-30 13F MIRION TECHNOLOGIES COM CL A 60471A101 189,844 -261,630 -57.95 4,416 -54.58 0.0007
2025-08-14 2025-06-30 13F MIRION TECHNOLOGIES COM CL A 60471A101 451,474 -457,778 -50.35 9,720 -26.27 0.0017
2025-05-15 2025-03-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 909,252 798,015 717.40 13,184 579.24 0.0025
2025-02-14 2024-12-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 111,237 87,975 378.19 1,941 655.25 0.0003
2024-11-14 2024-09-30 13F MIRION TECHNOLOGIES COM CL A 60471A101 23,262 23,262 258 0.0000
2024-08-14 2024-06-30 13F MIRION TECHNOLOGIES COM CL A 60471A101 0 -60,340 -100.00 0 -100.00
2024-05-15 2024-03-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 60,340 10,004 19.87 686 33.20 0.0001
2024-02-14 2023-12-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 50,336 -387,567 -88.51 516 -84.26 0.0001
2023-11-14 2023-09-30 13F MIRION TECHNOLOGIES COM CL A 60471A101 437,903 426,054 3,595.70 3,271 3,171.00 0.0007
2023-08-14 2023-06-30 13F MIRION TECHNOLOGIES COM CL A 60471A101 11,849 11,849 100 0.0000
2023-05-15 2023-03-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 0 -5,496 -100.00 0 -100.00
2023-02-14 2022-12-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 5,496 5,496 36 0.0000
2022-08-15 2022-06-30 13F MIRION TECHNOLOGIES COM CL A 60471A101 0 -368,946 -100.00 0 -100.00
2022-05-16 2022-03-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 368,946 262,497 246.59 2,978 167.09 0.0006
2022-02-14 2021-12-31 13F MIRION TECHNOLOGIES COM CL A 60471A101 106,449 106,449 1,115 0.0002
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F MIRION TECHNOLOGIES COM CL A Call 209,400 -28.46 3,893 -43.22 n/a n/a n/a
2026-02-17 2025-12-31 13F MIRION TECHNOLOGIES COM CL A Call 292,700 180.63 6,855 182.56 n/a n/a n/a
2025-11-14 2025-09-30 13F MIRION TECHNOLOGIES COM CL A Call 104,300 117.75 2,426 135.31 n/a n/a n/a
2025-08-14 2025-06-30 13F MIRION TECHNOLOGIES COM CL A Call 47,900 -28.61 1,031 6.07 n/a n/a n/a
2025-05-15 2025-03-31 13F MIRION TECHNOLOGIES COM CL A Call 67,100 115.76 973 79.34 n/a n/a n/a
2025-02-14 2024-12-31 13F MIRION TECHNOLOGIES COM CL A Call 31,100 1,729.41 543 2,911.11 n/a n/a n/a
2024-11-14 2024-09-30 13F MIRION TECHNOLOGIES COM CL A Call 1,700 -37.04 19 -35.71 n/a n/a n/a
2024-08-14 2024-06-30 13F MIRION TECHNOLOGIES COM CL A Call 2,700 -94.78 29 -95.23 n/a n/a n/a
2024-05-15 2024-03-31 13F MIRION TECHNOLOGIES COM CL A Call 51,700 -66.34 588 -62.71 n/a n/a n/a
2024-02-14 2023-12-31 13F MIRION TECHNOLOGIES COM CL A Call 153,600 -0.90 1,574 36.04 n/a n/a n/a
2023-11-14 2023-09-30 13F MIRION TECHNOLOGIES COM CL A Call 155,000 -25.16 1,158 -33.85 n/a n/a n/a
2023-08-14 2023-06-30 13F MIRION TECHNOLOGIES COM CL A Call 207,100 -21.58 1,750 -22.44 n/a n/a n/a
2023-05-15 2023-03-31 13F MIRION TECHNOLOGIES COM CL A Call 264,100 92.49 2,255 148.90 n/a n/a n/a
2023-02-14 2022-12-31 13F MIRION TECHNOLOGIES COM CL A Call 137,200 -30.43 907 -38.49 n/a n/a n/a
2022-11-14 2022-09-30 13F MIRION TECHNOLOGIES COM CL A Call 197,200 103.09 1,473 163.51 n/a n/a n/a
2022-08-15 2022-06-30 13F MIRION TECHNOLOGIES COM CL A Call 97,100 -32.24 559 -51.64 n/a n/a n/a
2022-05-16 2022-03-31 13F MIRION TECHNOLOGIES COM CL A Call 143,300 -43.96 1,156 -56.82 n/a n/a n/a
2022-02-14 2021-12-31 13F MIRION TECHNOLOGIES COM CL A Call 255,700 2,677 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F MIRION TECHNOLOGIES COM CL A Put 16,200 -78.28 301 -82.77 n/a n/a n/a
2026-02-17 2025-12-31 13F MIRION TECHNOLOGIES COM CL A Put 74,600 -63.84 1,747 -63.59 n/a n/a n/a
2025-11-14 2025-09-30 13F MIRION TECHNOLOGIES COM CL A Put 206,300 -6.14 4,799 1.39 n/a n/a n/a
2025-08-14 2025-06-30 13F MIRION TECHNOLOGIES COM CL A Put 219,800 370.66 4,732 598.97 n/a n/a n/a
2025-05-15 2025-03-31 13F MIRION TECHNOLOGIES COM CL A Put 46,700 -35.05 677 -46.01 n/a n/a n/a
2025-02-14 2024-12-31 13F MIRION TECHNOLOGIES COM CL A Put 71,900 43.80 1,255 126.76 n/a n/a n/a
2024-11-14 2024-09-30 13F MIRION TECHNOLOGIES COM CL A Put 50,000 -8.93 554 -6.11 n/a n/a n/a
2024-08-14 2024-06-30 13F MIRION TECHNOLOGIES COM CL A Put 54,900 240.99 590 221.86 n/a n/a n/a
2024-05-15 2024-03-31 13F MIRION TECHNOLOGIES COM CL A Put 16,100 -12.50 183 -2.66 n/a n/a n/a
2024-02-14 2023-12-31 13F MIRION TECHNOLOGIES COM CL A Put 18,400 327.91 189 487.50 n/a n/a n/a
2023-11-14 2023-09-30 13F MIRION TECHNOLOGIES COM CL A Put 4,300 -32.81 32 -40.74 n/a n/a n/a
2023-08-14 2023-06-30 13F MIRION TECHNOLOGIES COM CL A Put 6,400 -20.00 54 -20.59 n/a n/a n/a
2023-05-15 2023-03-31 13F MIRION TECHNOLOGIES COM CL A Put 8,000 -61.35 68 -50.00 n/a n/a n/a
2023-02-14 2022-12-31 13F MIRION TECHNOLOGIES COM CL A Put 20,700 32.69 137 16.24 n/a n/a n/a
2022-11-14 2022-09-30 13F MIRION TECHNOLOGIES COM CL A Put 15,600 -7.69 117 20.62 n/a n/a n/a
2022-08-15 2022-06-30 13F MIRION TECHNOLOGIES COM CL A Put 16,900 -70.76 97 -79.18 n/a n/a n/a
2022-05-16 2022-03-31 13F MIRION TECHNOLOGIES COM CL A Put 57,800 -1.20 466 -23.98 n/a n/a n/a
2022-02-14 2021-12-31 13F MIRION TECHNOLOGIES COM CL A Put 58,500 613 n/a n/a n/a
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.