Form 4 Tracker
Atlas Venture Fund X, L.P.

10% Owner · 1 filing · Latest: Feb 9, 2026

Generation Bio Co.
TickerOwnerRelationshipDateTransactionCost#SharesValue ($)#Shares TotalSEC Filing
KYMR
Atlas Venture Fund X, LPApr 22, 2026
Proposed Sale
$88.0788$7.8K
KYMR
Atlas Venture Fund X, LPApr 15, 2026
Proposed Sale
$89.872,750$247.1K
KYMR
Atlas Venture Fund X, LPMar 2, 2026
Proposed Sale
$91.35200,000$18.3M
IRON
Atlas Venture Fund X, LPDec 17, 2025
Proposed Sale
$91.47818$74.8K
IRON
Atlas Venture Fund X, LPDec 16, 2025
Proposed Sale
$92.0022,666$2.1M
IRON
Atlas Venture Fund X, L.P.Dec 16, 2025
Proposed Sale
$91.4752,000$4.8M
IRON
Atlas Venture Fund X, L.P.Dec 15, 2025
Proposed Sale
$92.0036,877$3.4M
IRON
Atlas Venture Fund X, LPDec 15, 2025
Proposed Sale
$91.8532,035$2.9M
IRON
Atlas Venture Fund X, LPDec 12, 2025
Proposed Sale
$93.6049,299$4.6M
KYMR
Atlas Venture Fund X, L.P.Dec 12, 2025
Proposed Sale
$89.68570$51.1K
KYMR
Atlas Venture Fund X, L.P.Dec 11, 2025
Proposed Sale
$87.815,125$450.0K
KYMR
Atlas Venture Fund X, L.P.Dec 10, 2025
Proposed Sale
$89.89193,040$17.4M
IRON
Atlas Venture Fund X, LPOct 17, 2025
Proposed Sale
$74.3650,000$3.7M
IRON
Atlas Venture Fund X, LPOct 16, 2025
Proposed Sale
$76.981,425$109.7K
IRON
Atlas Venture Fund X, LPOct 15, 2025
Proposed Sale
$73.0022,160$1.6M
IRON
Atlas Venture Fund X, L.P.Aug 22, 2025
Proposed Sale
$59.754,080$243.8K
IRON
Atlas Venture Fund X, L.P.Aug 14, 2025
Proposed Sale
$61.1012,862$785.9K
IRON
Atlas Venture Fund X, L.P.Aug 13, 2025
Proposed Sale
$59.0344,520$2.6M
IRON
Atlas Venture Fund X, L.P.Aug 5, 2025
Proposed Sale
$59.79705$42.2K
IRON
Atlas Venture Fund X, L.P.Jul 30, 2025
Proposed Sale
$59.8015,146$905.7K

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