Ticker · CUSIP 589889104
···Share
Holders (tracked)
15
Combined shares
5,871,827
Combined value
$460.76M
Last close
Quarter
2025Q4
Tracked holders · last 8 quarters
+4 vs previous quarter over the last 8.
15142024Q12025Q4

SEC event timeline

24 events
  1. −83,194 shares · 2025Q4
    Position
  2. +4,704 shares · 2025Q4
    Position
  3. +37,961 shares · 2025Q4
    Position
  4. −63,370 shares · 2025Q4
    Position
  5. +436,531 shares · 2025Q4
    Position
  6. +4,016 shares · 2025Q4
    Position
  7. +86,504 shares · 2025Q4
    Position
  8. +6,800 shares · 2025Q4
    Position
  9. +3,825 shares · 2025Q4
    Position
  10. −1,124,048 shares · 2025Q4
    Position
  11. +51,300 shares · 2025Q4
    Position
  12. +861,781 shares · 2025Q4
    Position
  13. −16,606 shares · 2025Q4
    Position
  14. −101,265 shares · 2025Q3
    Position
  15. +6,772 shares · 2025Q3
    Position
  16. −216,188 shares · 2025Q3
    Position
  17. −331,435 shares · 2025Q3
    Position
  18. +230,806 shares · 2025Q3
    Position
  19. −91,497 shares · 2025Q3
    Position
  20. +980,823 shares · 2025Q3
    Position
  21. −96,000 shares · 2025Q3
    Position
  22. −574,422 shares · 2025Q3
    Position
  23. +6,164 shares · 2025Q3
    Position
  24. −48,036 shares · 2024Q3
    Position

Insider activity

No insider transactions in the last 30 days.

Who moved on this name in 2025Q4

Position changes reported for the latest quarter, grouped by direction.

Institutional ownership over time

Distinct super-investors holding this ticker · combined dollar value, by quarter.
QuarterHoldersCombined value
2022Q1
13
$29.43B
2022Q2
14
$27.79B
2022Q3
11
$30.0M
2022Q4
11
$755.4M
2023Q1
12
$830.8M
2023Q2
14
$987.9M
2023Q3
15
$812.6M
2023Q4
15
$906.6M
2024Q1
14
$866.9M
2024Q2
16
$1.04B
2024Q3
14
$244.7M
2024Q4
14
$255.4M
2025Q1
13
$401.4M
2025Q2
12
$490.5M
2025Q3
11
$414.6M
2025Q4
15
$460.8M
Congress members trading this stock
DateMemberTypeAmount rangeFiling
2025-09-25Lisa McClainSell$1K – $15KPDF ↗
2025-07-22Lisa McClainBuy$1K – $15KPDF ↗

Who owns MMSI

15 super-investors · 2025Q4
Tracked stake
5.87M
shares
Combined value
$461M
% of shares outstanding
shares-out unknown
Quarter action mix
New3Added6Trim6
#ManagerSharesValue
1Wellington Management1.33M$117M
2Ken Griffin
Citadel Advisors
1.09M$96M
3Norges Bank
Norway SWF
861.8K$76M
4Lee Ainslie
Maverick Capital
486.2K$43M
5Steve Cohen
Point72
436.5K$38M
6Two Sigma Investments379.7K$33M
7Ken Fisher
Fisher Asset Mgmt
205.0K$18M
8D.E. Shaw & Co.197.7K$17M
9Renaissance Technologies126.2K$11M
10Izzy Englander
Millennium Mgmt
50.0K$4M
11Izzy Englander
Millennium Mgmt
26.3K$2M
12AQR Capital Management24.8K$2M
13Paul Tudor Jones
Tudor Investment
6.8K$599K
14Ken Griffin
Citadel Advisors
5.4K$476K
15T. Rowe Price644.9K$57K

Recent moves

20 transactions
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