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BLLNHealth CareCommon Stock

BillionToOne, Inc (Class A)

Held by 10 tracked managers as of Q2 2026 · CUSIP ⓘCUSIP: A 9-character ID for one specific security - one share class of one company, or one bond. Tickers can change and can mean different things in different countries; a CUSIP always identifies exactly the same security, which is why filings use it. Guide 090168105 · Sector ⓘGICS sectors: The 11-sector system most investors know (Global Industry Classification Standard): Technology, Health Care, Financials and so on. This site assigns each company a GICS-style sector from its SIC code, with a few hand corrections, so sector pages match the names investors expect. Guide

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In plain English: 10 of the investors we track own this stock. In the latest quarter, 8 of them bought more of it and 3 sold some or all of theirs (4 bought it for the first time). That tells you what they did last quarter — not what the stock will do next.

Educational and informational only, not personalized investment advice. Based on public filings that may be delayed or contain errors; verify with the original filings. Disclaimer

Managers holding
10
+3 vs last quarter (like-for-like)
Total value held
$346.22M
Across tracked managers
Average weight ⓘOn average, how big this stock is in the portfolios that own it (its share of each manager's reported portfolio value).
0.1%
Of each manager's book
QoQ value ⓘLike-for-like: only managers that filed both quarters are compared, so a manager filing late (or confidentially) does not look like buying or selling. Includes price changes.
+$147.01M
+73.8% vs last quarter
Net shares bought
+362.1K
Est. net flow +$44.04M
Quarter activity
8 bought · 3 sold
4 new · 1 sold out

Tracked capital in this stock

Total value held (area) and number of managers (line). Dips can mean a large holder filed that quarter confidentially (e.g. Norges Bank in Q1/Q3).

Chart: Tracked capital in this stock

Aggregate buying and selling

Net share change reported each quarter

Chart: Aggregate buying and selling

Who owns BLLN?

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Who owns BLLN? — Q2 2026

Holders ranked by position size, with each one's quarter-over-quarter change.

CSV Excel
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Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

# Manager Fund Shares Value ↓ % of their portfolio QoQ Δ shares Δ shares % Est. Δ value ⓘChange in shares × this quarter's price
1 Baillie Gifford Baillie Gifford & Co 901.42K $108.15M 0.1% Reduced -358.6K -28.5% -$43.02M
2 Ron Baron Baron Capital (BAMCO) 742.09K $89.04M 0.1% Added +608 +0.1% +$72.95K
3 Wasatch Advisors Wasatch Advisors LP 518.08K $62.16M 0.4% Added +148.4K +40.2% +$17.81M
4 Israel Englander Millennium Management 425.03K $51.00M 0.0% New +425.0K — +$51.00M
5 Fred Alger Fred Alger Management 114.12K $13.69M 0.0% New +114.1K — +$13.69M
6 Jim Simons Renaissance Technologies 96.60K $11.59M 0.0% Added +45.3K +88.5% +$5.44M
7 Two Sigma Two Sigma Investments 30.18K $3.62M 0.0% Reduced -52.6K -63.5% -$6.31M
8 David Shaw D.E. Shaw & Co. 25.98K $3.12M 0.0% Added +22.1K +572.7% +$2.65M
9 Polen Capital Polen Capital Management 16.98K $2.04M 0.0% New +17.0K — +$2.04M
10 Ken Griffin Citadel Advisors 15.15K $1.82M 0.0% New +15.2K — +$1.82M

Sold out completely this quarter

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

Manager Fund Shares sold Value last quarter ↓
George Soros Soros Fund Management -14.5K $1.14M

Politician trades

Politician trades in BLLN

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

No politician trades match these filters.