Ticker · CUSIP 37148K100

GBIOGBX

GENERATION BIO CO
···Share
Holders (tracked)
7
Combined shares
12,582,407
Combined value
$4.03M
Last close
Quarter
2025Q2
Tracked holders · last 8 quarters
Flat over the last 8 quarters.
782023Q32025Q2

SEC event timeline

5 events
  1. −1,061,606 shares · 2025Q3
    Position
  2. −105,961 shares · 2025Q3
    Position
  3. −8,462,611 shares · 2025Q3
    Position
  4. −63,689 shares · 2025Q3
    Position
  5. −2,580,780 shares · 2025Q3
    Position

Insider activity

No insider transactions in the last 30 days.

Who moved on this name in 2025Q2

Position changes reported for the latest quarter, grouped by direction.
New positions1
Added to2
Trimmed2
Exited0

Institutional ownership over time

Distinct super-investors holding this ticker · combined dollar value, by quarter.
QuarterHoldersCombined value
2021Q3
3
$294.9M
2021Q4
7
$69.9M
2022Q1
7
$91.2M
2022Q2
8
$85.7M
2022Q3
9
$61.8M
2022Q4
8
$45.1M
2023Q1
8
$49.6M
2023Q2
9
$63.2M
2023Q3
8
$42.4M
2023Q4
7
$19.8M
2024Q1
7
$53.7M
2024Q2
10
$40.7M
2024Q3
4
$26.1M
2024Q4
8
$11.6M
2025Q1
7
$4.6M
2025Q2
7
$4.0M

Who owns GBIOGBX

7 super-investors · 2025Q2
Tracked stake
12.58M
shares
Combined value
$4M
% of shares outstanding
shares-out unknown
Quarter action mix
New1Added2Trim2Held2
#ManagerSharesValue
1T. Rowe Price8.46M$3M
2Renaissance Technologies2.58M$826K
3Izzy Englander
Millennium Mgmt
1.06M$340K
4Ken Griffin
Citadel Advisors
192.2K$62K
5Ken Griffin
Citadel Advisors
115.6K$37K
6Two Sigma Investments106.0K$34K
7AQR Capital Management63.7K$20K

Recent moves

20 transactions
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