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, LPJun 29, 2026
Proposed Sale
$108.1266,177$7.2M
KYMR
Atlas Venture Fund X, LPJun 26, 2026
Proposed Sale
$116.46410,427$47.8M
KYMR
Atlas Venture Fund X, LPJun 25, 2026
Proposed Sale
$99.87480,992$48.0M
KYMR
Atlas Venture Fund X, LPJun 24, 2026
Proposed Sale
$98.25118,178$11.6M
KYMR
Atlas Venture Fund X, LPJun 23, 2026
Proposed Sale
$99.451,235$122.8K
KYMR
Atlas Venture Fund X, LPJun 22, 2026
Proposed Sale
$90.43243,976$22.1M
KYMR
Atlas Venture Fund X, LPJun 18, 2026
Proposed Sale
$89.90100,928$9.1M
KYMR
Atlas Venture Fund X, LPJun 17, 2026
Proposed Sale
$87.4492,169$8.1M
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

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