• Unity Screen: A non-invasive prenatal test (NIPT) that screens for common chromosomal aneuploidies, microdeletions, and recessive conditions from a single maternal blood draw.
• Northstar Select: A liquid biopsy test used for comprehensive genomic profiling in oncology applications, enabling detection of tumor DNA mutations from a blood sample.

BillionToOne (BLLN) - Major Customers

BillionToOne (BLLN) is a molecular diagnostics company that specializes in developing and offering genetic tests for prenatal screening, oncology, and infectious diseases. The company's services are primarily delivered through its CLIA-certified laboratory, making its business model primarily business-to-business (B2B).

According to BillionToOne's public filings, no single customer accounts for more than 10% of its total revenue. This indicates a highly diversified customer base rather than a reliance on a few large "major customer companies." As such, BillionToOne does not publicly disclose a limited list of specific major customer companies, nor are there identifiable public companies that represent a significant concentration of their revenue.

Instead, BillionToOne serves a broad network of healthcare entities that utilize and order their diagnostic tests. These customer categories include:

• Physician Practices and Clinics: This includes OB/GYN offices, maternal-fetal medicine specialists, and oncology clinics that refer their patients for BillionToOne's genetic testing services.
• Hospitals and Hospital Systems: Healthcare institutions that may integrate BillionToOne's advanced diagnostic tests into their broader patient care offerings.
• Reference Laboratories: Other diagnostic laboratories that may partner with BillionToOne or send out specialized testing to BillionToOne's facility.

Oguzhan Atay Co-Founder, CEO, and Board Chair

Oguzhan Atay co-founded BillionToOne in 2016 and believes in making diagnostics more powerful, accurate, and affordable through quantitative engineering. He holds a PhD in Systems Biology from Stanford University, where his research, featured as a Cover Article in Cell Systems, combined machine learning and genetics to address cell biology problems. He also earned a Bachelor's in Molecular Biology from Princeton University (summa cum laude, Phi Beta Kappa) with minors in Physics, Computer Science, and Applied Mathematics. Atay took BillionToOne through Y Combinator (S17) and successfully raised significant funding. Under his leadership, BillionToOne went public on the Nasdaq stock exchange in November 2025.

Ross Taylor Chief Financial Officer

Ross Taylor joined BillionToOne as Chief Financial Officer in January 2024, bringing 30 years of financial leadership experience. He previously served as CFO for Codexis, Inc. from 2019 to 2023. From August 2015 to July 2018, Taylor was CFO of Abaxis, Inc. until its acquisition by Zoetis. Before his CFO role at Abaxis, he was its Vice President of Business Development & Investor Relations. Taylor also spent 20 years in equity research on Wall Street with firms such as CL King & Associates, UBS, Smith Barney, and CJ Lawrence, specializing in life sciences, healthcare, and diagnostics. He holds an MBA from Columbia Business School and a Bachelor's in Economics from Duke University.

David Tsao Co-Founder, CTO, and Board Member

David Tsao is a co-founder of BillionToOne and the original inventor of the company's molecular counting platform. He oversees all technology developments at the company. Tsao earned a PhD in bioengineering from Rice University and a bachelor's degree in physics (cum laude) from Princeton University, with minors in biophysics and engineering management systems. Before his doctoral studies, he worked as a software engineer at Adku and Groupon, where he developed recommendation engines and search engine marketing solutions using big data.

John Lister Chief Administrative Officer

John Lister serves as BillionToOne's Chief Administrative Officer, leading the People, Legal, IT, and RA/QA teams. Prior to BillionToOne, he held various leadership positions at Dexcom, a continuous glucose monitoring company, where he was part of the executive leadership team. During his tenure at Dexcom, he led the Legal, People, and International teams, contributing to the company's growth from 70 to over 6,000 employees and from $0 to over $1.5 billion in revenue. Most recently, Lister was the Chief Operating Officer for Tidepool, a diabetes software startup.

Shan Riku Chief Product Officer

Shan Riku is the Chief Product Officer at BillionToOne. She holds an MBA.

Key Risks to BillionToOne (BLLN)

1. Intense Competition

   BillionToOne operates in highly competitive markets for both its prenatal screening (UNITY) and oncology diagnostics (Northstar) platforms. In the non-invasive prenatal testing (NIPT) market, the company faces established players such as Natera, LabCorp/Sequenom, Quest Diagnostics, Myriad Genetics, and Illumina. Natera, for instance, dominates the U.S. NIPT market with approximately 60% market share. Similarly, the liquid biopsy space for oncology diagnostics is crowded with significant competitors including Guardant Health, Foundation Medicine, Tempus AI, GRAIL, and Exact Sciences. The company's ability to maintain and grow market share in these competitive landscapes, despite its differentiated Quantitative Counting Template (QCT) technology, remains a key risk.

2. Regulatory and Reimbursement Uncertainties

   As a precision diagnostics company in the healthcare sector, BillionToOne is susceptible to significant regulatory changes and uncertainties surrounding reimbursement policies for its genetic tests. Changes in diagnostic guidelines or reimbursement rates from healthcare providers and insurers could directly impact the company's revenue and profitability. While BillionToOne's UNITY prenatal screen leverages existing CPT codes for carrier testing reimbursement, ongoing shifts in the complex reimbursement landscape pose a continuous risk.

3. Financial Health and Operational Challenges

   Despite strong revenue growth projections and liquidity, BillionToOne faces financial and operational challenges. The company has reported a negative operating margin, indicating ongoing operational hurdles, and a Z-Score of 0, which suggests potential financial distress. Furthermore, the identification of material weaknesses in internal controls over financial reporting is a critical issue that, if unresolved, could affect investor confidence and share price. The company anticipates increased expenses and future capital requirements to support its growth strategy, likely necessitating additional financing.

The accelerated development and potential widespread adoption of highly sensitive and specific Multi-Cancer Early Detection (MCED) tests by well-funded competitors (e.g., Grail/Illumina, Guardant Health, Exact Sciences) represents a clear emerging threat. These tests aim to detect multiple cancers at very early stages from a single blood draw, which could significantly shift the paradigm for cancer screening and diagnosis. As BillionToOne offers Northstar Select, an oncology liquid biopsy test, the rise of superior and widely adopted MCED tests could redefine the standard of care, potentially making other oncology liquid biopsy applications less competitive or altering market demand.

BillionToOne (BLLN) operates in the molecular diagnostics market, with its main products addressing prenatal screening and oncology liquid biopsies. The company estimates its total addressable market in the U.S. to be approximately $100 billion.

• For its prenatal testing products, such as UNITY Complete®, the addressable market is estimated at $5 billion in the U.S.
• For its oncology liquid biopsy products, including Northstar Select® and Northstar Response®, the market for cancer therapy selection, therapy monitoring, and post-treatment surveillance is estimated to be over $50 billion in the U.S. Specifically, the market for late-stage cancers is estimated at over $20 billion, with an additional $30 billion opportunity for a tumor-naive minimal residual disease test.

Here are the expected drivers of future revenue growth for BillionToOne (symbol: BLLN) over the next 2-3 years:

1. Growth in Test Volume and Average Selling Prices (ASPs): BillionToOne expects continued robust growth in the volume of tests delivered across both its prenatal and oncology segments. This growth is complemented by an anticipated increase in average selling prices for its diagnostic tests, which has significantly contributed to past revenue increases.
2. Launch and Expansion of New Products and Services: The company plans to launch a best-in-class tumor-naive molecular residual disease (MRD) test by the end of 2026, which is expected to be a significant driver of future growth. Additionally, recently launched products like Northstar Select PGx and Northstar Select CH, along with expanded Red Blood Cell Fetal Antigen (NIPT) and Platelet Fetal Antigen (NIPT) offerings, are projected to contribute to revenue growth.
3. Expanded Payer Coverage and Market Access: Future revenue growth is anticipated from securing expanded payer contracts and gaining MolDX coverage for its Northstar Response oncology test. These developments are crucial for increasing accessibility and adoption of BillionToOne's diagnostic solutions.
4. Sales Force Expansion and Increased Provider Awareness: BillionToOne is actively expanding its sales force and implementing initiatives to increase awareness among healthcare providers regarding its innovative molecular testing technologies. This strategic expansion is aimed at driving higher adoption rates and test volumes in both existing and new markets.