BillionToOne CEO Liquidates Entire Directly-Held Stake in the Company for $3 Million

Oguzhan Atay, Chairman and Chief Executive Officer of BillionToOne, Inc. (NASDAQ:BLLN), sold 30,331 shares of Class A Common Stock on September 14, 2026, for a total value of ~$3 million, as disclosed in a recent SEC Form 4 filing.

Transaction summary

Metric	Value
Transaction value	~$3.0 million
Shares sold	30,331
Shares sold (directly held)	24,999
Shares sold (indirectly held)	5,332
Post-transaction shares (directly held)	0
Post-transaction shares (indirectly held)	157,168
Post-transaction value	$15.85 million

Transaction value based on SEC Form 4 weighted average sale price ($99.91); post-transaction value based on September 14, 2026 market close ($100.82).

Key questions

• What were the specifics of this transaction?
  The disposition was primarily driven by the cash-less exercise of 24,999 options at a strike price of $2.80, with the resulting shares sold immediately. Additionally, 5,332 shares were sold from an account held by the reporting person's spouse.
• How does the execution price align with recent market performance?
  The sales were executed at a weighted average price of $99.91, while the stock has since appreciated to $103.61 as of the September 16, 2026 market close.
• To what extent was this activity pre-planned?
  The transactions followed Rule 10b5-1 trading plans adopted by Atay on June 5, 2026, and by the insider's spouse on June 7, 2026, which removes discretionary timing from the trade execution.
• What is the insider's residual equity exposure?
  Following the completion of these sales, Atay holds ~157,000 shares indirectly through a spouse and retains ~500,000 direct derivative securities, which are fully vested.

Company Overview

Metric	Value
Share Price (as of market close 2026-09-16)	$103.61
Market Capitalization	$4.8 billion
Revenue (TTM)	$397.4 million
Net Income (TTM)	$33.5 million

Company Snapshot

• BillionToOne develops and commercializes advanced molecular diagnostic solutions, with primary products including Unity, a non-invasive prenatal screening test that leverages proprietary DNA molecule quantification technology to assess fetal risk for chromosomal abnormalities.
• The company generates revenue through the sale of diagnostic tests and related services, utilizing its proprietary molecular counting platform to deliver enhanced precision in disease detection and risk stratification across multiple clinical applications.
• BillionToOne serves healthcare providers, genetic counselors, and patients seeking advanced prenatal and molecular diagnostic testing, with a target market encompassing reproductive health, oncology, and other precision medicine segments.

BillionToOne is a specialized diagnostics company with a market cap of $4.8 billion. The company's competitive advantage derives from its proprietary molecular counting platform, which enables precise quantification of individual DNA molecules to significantly enhance diagnostic accuracy.

Based in Menlo Park, BillionToOne is positioned as an innovator in precision molecular diagnostics, addressing the growing demand for non-invasive and highly accurate disease detection solutions.

What this transaction means for investors

BillionToOne CEO Oguzhan Atay's September 14 sale of company shares is noteworthy because he disposed of his entire stake of directly held shares, and his spouse sold 5,332 shares as well. While this substantial disposition can be concerning for investors, it was executed as part of a pre-established Rule 10b5-1 plan, making the move by Atay and his spouse a non-discretionary transaction.

In addition, Atay retains 501,962 fully vested stock options after this sale, a sizable sum that ensures his continued alignment with shareholder interests. His spouse maintains 157,168 shares, post-transaction.

BillionToOne is doing well. It reported revenue of $109.4 million in the second quarter of 2026. This is 64% year-over-year growth, demonstrating that demand for its diagnostic capabilities is strong.

The company expects sales to continue growing. It forecasted full year 2026 revenue to come in between $450 million and $465 million, representing an increase of 48% to 52% compared to 2025.

Robert Izquierdo has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends BillionToOne. The Motley Fool has a disclosure policy.