Atlas Venture Opportunity Fund II, L.P.

CIK 1885327 · last filed 2025-02-10

"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

$219.22M

Companies

2

Total Filings

48

Lifetime Open-Market Net

-$95.58M

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
SION 10%+ Owner 3,694,020 $5.94 $21.94M $6.48M 1 2025-02-10
DYN 10%+ Owner 7,587,471 $26.00 $197.27M -$102.06M 1 2024-02-23

Recent Filings · Page 4 of 5

48 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
2025-12-12 IRON Notice (144) −12,325 -$1.15M EDGAR
2025-10-21 SION Notice (144) −15,418 -$496.5K EDGAR
2025-10-20 SION Notice (144) −9,712 -$310.1K EDGAR
2025-10-17 SION Notice (144) −10,604 -$346.9K EDGAR
2025-10-17 IRON Notice (144) −35,000 -$3.15M EDGAR
2025-10-16 SION Notice (144) −29,363 -$907.6K EDGAR
2025-10-14 SION Notice (144) −10,102 -$297.2K EDGAR
2025-10-10 SION Notice (144) −3,511 -$99.5K EDGAR
2025-10-06 SION Notice (144) −2,047 -$61.4K EDGAR
2025-10-03 SION Notice (144) −6,548 -$191.9K EDGAR
Showing 3140 of 48
Page 4 of 5
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.