BillionToOne Raises $273M in Upsized IPO Amid Strong Investor Demand
The molecular diagnostics firm priced its offering at $60 per share, signaling robust appetite for specialized biotech companies in a selective market.
BillionToOne, a precision diagnostics company, announced Wednesday evening it had priced an upsized initial public offering, raising approximately $273.1 million in a sign of strong investor confidence in the specialized healthcare sector. The company sold 4.55 million shares at $60.00 apiece, a figure that points to significant demand uncovered during its investor roadshow.
The offering, which was increased from its initial size, provides a notable data point on the health of the biotech IPO market, which has been characterized by cautious optimism throughout 2025. Shares are expected to begin trading Thursday on the Nasdaq Global Select Market under the ticker symbol “BLLN”.
Based in Menlo Park, California, BillionToOne operates at the intersection of molecular biology and data science. The company has developed a proprietary diagnostics platform, known as Quantitative Counting Templates (QCT™), which it claims can detect and measure disease at the molecular level with greater precision. This technology underpins its two main commercial offerings: prenatal screening and liquid biopsy for oncology.
Its flagship prenatal product, the UNITY Screen, is a non-invasive test that screens for a range of genetic conditions in a fetus, such as cystic fibrosis and spinal muscular atrophy. The company has focused on expanding its capabilities, launching an expanded panel in May 2025 to set a new standard in prenatal care.
In the oncology space, BillionToOne’s Northstar platform offers liquid biopsy tests—which detect cancer signals from tumor DNA circulating in the blood—to help guide therapy selection and monitor treatment response for cancer patients. This places it in a rapidly growing, but intensely competitive, field alongside established players like Natera, Illumina, and Guardant Health.
The decision to upsize the IPO suggests that underwriters, including Morgan Stanley and J.P. Morgan, found demand exceeded the initial number of shares allocated. This is often viewed as a bullish signal, indicating that institutional investors are confident in the company's growth story and its technological edge. According to a company press release, the offering is expected to close on November 10, 2025, subject to customary closing conditions.
BillionToOne’s public debut comes as investors have become more selective, favoring biotech firms with strong clinical data and a clear path to commercialization. After a slowdown in early 2025, the market has seen a cautious resurgence in biotech offerings, with a focus on companies that can demonstrate both innovation and a solid business model.
The nearly $273 million in gross proceeds will provide significant capital for BillionToOne to advance its strategic priorities. The company is expected to use the funds to scale up its commercial operations, invest further in research and development for its QCT platform, and expand its sales and marketing efforts to capture a larger share of the diagnostics market.
As BillionToOne enters the public markets, investors will be closely watching its ability to grow revenue, manage cash burn, and navigate the competitive landscapes of both prenatal and oncology testing. The successful IPO provides the financial runway; now the focus will turn to execution.