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Ken Griffin's Mirion Technologies, Inc. (MIR) position

Yes: as of Q1 2026, Ken Griffin holds 1.8M shares of MIR worth $34M (0.0% of the disclosed portfolio). Last quarter the position was increased by 12.5%. First disclosed Q4 2021.
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Current value
$34M
Shares held
1.8M
% of portfolio
0.0%
Est. average buy price (i)
$23.70
Quarter-end price
$18.59

Estimated trade prices

Average price in quarters with purchases
$18.25
Average prices in quarters with sales
  • Q3 2025: $21.62 (262K shares sold)
  • Q2 2025: $17.24 (458K shares sold)
  • Q4 2023: $8.44 (388K shares sold)

MIR price vs Griffin's position

1Y 3Y 5Y MAX
Dates
$5$20$4020222023202420252026New position of 106K shares · Q4 2021. Average closing price $10.74 · Price range $9.84–$11.76106KsharespurchasedAdded 262K shares (246.6%) · Q1 2022. Average closing price $8.61 · Price range $7.58–$10.71262KsharespurchasedNew position of 5K shares · Q4 2022. Average closing price $6.73 · Price range $5.70–$8.205KsharespurchasedNew position of 12K shares · Q2 2023. Average closing price $8.11 · Price range $7.44–$8.5112KsharespurchasedAdded 426K shares (over 1,000%) · Q3 2023. Average closing price $7.88 · Price range $7.38–$8.55426KsharespurchasedSold 388K shares (88.5%) · Q4 2023. Average closing price $8.44 · Price range $6.76–$10.49388KsharessoldAdded 10K shares (19.9%) · Q1 2024. Average closing price $10.02 · Price range $9.33–$11.3910KsharespurchasedNew position of 23K shares · Q3 2024. Average closing price $10.52 · Price range $9.45–$11.7823KsharespurchasedAdded 88K shares (378.2%) · Q4 2024. Average closing price $15.51 · Price range $10.94–$18.6588KsharespurchasedAdded 798K shares (717.4%) · Q1 2025. Average closing price $15.72 · Price range $13.51–$18.28798KsharespurchasedSold 458K shares (50.3%) · Q2 2025. Average closing price $17.24 · Price range $12.70–$21.71458KsharessoldSold 262K shares (58.0%) · Q3 2025. Average closing price $21.62 · Price range $19.79–$24.60262KsharessoldAdded 1.4M shares (753.7%) · Q4 2025. Average closing price $24.94 · Price range $22.57–$29.751.4MsharespurchasedAdded 202K shares (12.5%) · Q1 2026. Average closing price $22.56 · Price range $17.32–$27.00202Ksharespurchased
Average closing price · filing quarter
$22.56
Price range · filing quarter
$17.32 – $27.00
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Every quarterly change

Quarter Action Shares change Est. value change Δ Own Shares held Filing date
Q1 2026 Added +202K +$4.6M +12.5% 1.8M May 15, 2026
Q4 2025 Added +1.4M +$36M +753.7% 1.6M Feb 17, 2026
Q3 2025 Reduced −262K −$5.7M −58.0% 190K Nov 14, 2025
Q2 2025 Reduced −458K −$7.9M −50.3% 451K Aug 14, 2025
Q1 2025 Added +798K +$13M +717.4% 909K May 15, 2025
Q4 2024 Added +88K +$1.4M +378.2% 111K Feb 14, 2025
Q3 2024 New +23K +$245K – 23K Nov 14, 2024
Q1 2024 Added +10K +$100K +19.9% 60K May 15, 2024
Q4 2023 Reduced −388K −$3.3M −88.5% 50K Feb 14, 2024
Q3 2023 Added +426K +$3.4M +3,595.7% 438K Nov 14, 2023
Q2 2023 New +12K +$96K – 12K Aug 14, 2023
Q4 2022 New +5K +$37K – 5K Feb 14, 2023
Q1 2022 Added +262K +$2.3M +246.6% 369K May 16, 2022
Q4 2021 New +106K +$1.1M – 106K Feb 14, 2022
Data through Q1 2026 · filed May 15, 2026
14 grouped rows from 14 quarters

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Common questions

Does Ken Griffin own MIR?

Yes. As of Q1 2026, Ken Griffin disclosed 1.8M shares of MIR, worth $34M. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

When did Ken Griffin buy MIR?

Ken Griffin first disclosed a MIR position in Q4 2021; every quarterly buy and sell since is in the table above. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

Did Ken Griffin sell MIR?

The quarter-by-quarter table above shows each sale and reduction Ken Griffin disclosed in MIR. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

How many shares of MIR does Ken Griffin own?

Ken Griffin disclosed 1.8M shares of MIR as of Q1 2026. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

What price did Ken Griffin pay for MIR?

Ken Griffin's estimated average buy price for MIR is $23.70, from quarter-average prices weighted by the shares added each quarter. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.

How are the estimated trade prices calculated?

13F filings disclose quarter-end holdings, not trade dates or execution prices. These estimates use each covered quarter's average market price; the add average excludes the opening position and quarters without price data. All figures come from SEC 13F filings for Q1 2026, the latest disclosed quarter.