Ticker · CUSIP 04963C209
Holders (tracked)
10
Combined shares
5,786,008
Combined value
$226.90M
Last close
Quarter
2025Q4
Tracked holders · last 8 quarters
+2 vs previous quarter over the last 8.
10142024Q12025Q4

SEC event timeline

19 events
  1. +2,121 shares · 2025Q4
    Position
  2. −374,096 shares · 2025Q4
    Position
  3. −72,376 shares · 2025Q4
    Position
  4. +15,784 shares · 2025Q4
    Position
  5. −189,465 shares · 2025Q4
    Position
  6. +277,924 shares · 2025Q4
    Position
  7. +197,242 shares · 2025Q4
    Position
  8. +63,100 shares · 2025Q4
    Position
  9. +214,016 shares · 2025Q4
    Position
  10. +116,609 shares · 2025Q4
    Position
  11. −6,805 shares · 2025Q3
    Position
  12. +40,962 shares · 2025Q3
    Position
  13. −7,776 shares · 2025Q3
    Position
  14. +16,459 shares · 2025Q3
    Position
  15. +2,145 shares · 2025Q3
    Position
  16. +322,818 shares · 2025Q3
    Position
  17. −118,900 shares · 2025Q3
    Position
  18. −10,438 shares · 2025Q3
    Position
  19. −25,868 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.
New positions3
Trimmed3
Exited0

Institutional ownership over time

Distinct super-investors holding this ticker · combined dollar value, by quarter.
QuarterHoldersCombined value
2022Q1
11
$25.67B
2022Q2
13
$15.54B
2022Q3
12
$14.0M
2022Q4
14
$270.3M
2023Q1
13
$278.3M
2023Q2
14
$385.5M
2023Q3
13
$230.1M
2023Q4
13
$197.6M
2024Q1
14
$217.7M
2024Q2
14
$195.1M
2024Q3
12
$91.5M
2024Q4
10
$48.8M
2025Q1
11
$102.2M
2025Q2
10
$175.3M
2025Q3
8
$193.7M
2025Q4
10
$226.9M
Congress members trading this stock
DateMemberTypeAmount rangeFiling
2026-03-03Gilbert CisnerosBuy$1K – $15KPDF ↗
2025-05-06Gilbert CisnerosBuy$1K – $15KPDF ↗

Who owns ATRC

10 super-investors · 2025Q4
Tracked stake
5.79M
shares
Combined value
$227M
% of shares outstanding
shares-out unknown
Quarter action mix
New3Added4Trim3
#ManagerSharesValue
1Wellington Management3.92M$155M
2Two Sigma Investments380.5K$15M
3Renaissance Technologies321.9K$13M
4Steve Cohen
Point72
277.9K$11M
5Ken Griffin
Citadel Advisors
242.7K$10M
6Norges Bank
Norway SWF
214.0K$8M
7Izzy Englander
Millennium Mgmt
163.8K$6M
8First Eagle Investment Management116.6K$5M
9AQR Capital Management100.0K$4M
10T. Rowe Price50.6K$2K

Recent moves

20 transactions
Embed this chart
Paste this iframe anywhere to embed the live ATRC chart.
<iframe src="https://openstocks.me/embed/stock/ATRC" width="100%" height="480" frameborder="0" loading="lazy" title="ATRC chart by OpenStocks" style="border:0;border-radius:12px;background:transparent"></iframe>