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Atlas Venture Opportunity Fund I, L.P.

CIK 1759241 · last filed 2022-11-01

Atlas Venture Opportunity Fund I, L.P. is a corporate insider who has filed 74 SEC Form 4 insider transactions across 6 companies since 2019. The most recent filing, for DYN, was dated Jul 7, 2026. Across all open-market trades the lifetime net is −$54.6M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $744.2M across reported positions.

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$744.22M

Companies

6

Total Filings

74

Lifetime Open-Market Net

-$54.65M

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
KYMR 10%+ Owner 6,784,648 $109.62 $743.73M -$52.41M 1 2022-11-01
Day One Biopharmaceuticals, Inc. (DAWN) Delisted 10%+ Owner 793,116 $21.53 $17.08M $0 1 2022-07-06
XLO 10%+ Owner 52,567 $9.18 $482.6K $6.00M 1 2021-10-26
Generation Bio Co. (GBIO) Delisted 10%+ Owner 711,194 $5.34 $3.80M -$8.24M 1 2021-09-29
ImageneBio, Inc. (IKNA) Delisted 10%+ Owner 241,801 $17.16 $4.15M $0 1 2021-04-01
Akero Therapeutics, Inc. (AKRO) Delisted 10%+ Owner 404,079 $54.65 $22.08M $0 2 2020-02-10

Recent Filings

74 filings
Insider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
Filed Symbol Action Net Shares Net $ Link
2026-07-07 DYN Notice (144) −60,858 -$1.39M EDGAR
2026-07-06 DYN Notice (144) −100,019 -$2.31M EDGAR
2026-06-29 KYMR Notice (144) −10,473 -$1.13M EDGAR
2026-06-29 DYN Notice (144) −40,702 -$852.3K EDGAR
2026-06-26 DYN Notice (144) −64,411 -$1.33M EDGAR
2026-06-26 KYMR Notice (144) −57,451 -$6.69M EDGAR
2026-06-25 DYN Notice (144) −5,019 -$102.0K EDGAR
2026-06-25 KYMR Notice (144) −67,329 -$6.72M EDGAR
2026-06-24 DYN Notice (144) −19,973 -$404.7K EDGAR
2026-06-24 KYMR Notice (144) −16,542 -$1.63M EDGAR
Showing 1–10 of 74
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Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.