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Nov 5 (Reuters) - Molecular diagnostics firm BillionToOne BLLN.O raised $273.1 million in its U.S. initial public offering on Wednesday, pricing its shares above its marketed range.

The Menlo Park, California-based company sold about 4.6 million shares priced at $60 apiece in the IPO, compared with its targeted range of $49 and $55, giving it a potential valuation of about $2.64 billion.

The offering came as U.S. IPO activity rebounded after an earlier slowdown sparked by market volatility stemming from President Donald Trump's shifting trade policies.

Investor demand for new listings had risen, though the ongoing government shutdown caused temporary delays in the IPO pipeline.

Still, companies were able to proceed by using a provision that allowed registrations to take effect automatically, requiring pricing to be set 20 days before the listing rather than finalizing it the night before.

Last month, medical supplies giant Medline publicly filed for an IPO, a move that could encourage more healthcare and pharmaceutical companies to move forward with their own listing plans.

BillionToOne is a molecular diagnostics company that develops non-invasive prenatal and oncology blood tests using its single-molecule sequencing technology.

Unity is the company's prenatal testing offering, while its Northstar range targets cancer diagnosis.

BillionToOne will list on the Nasdaq under the "BLLN" ticker symbol.

J.P. Morgan, Piper Sandler, Jefferies and William Blair were among the underwriters for the offering.

(Reporting by Prakhar Srivastava and Bipasha Dey in Bengaluru; Editing by Mrigank Dhaniwala, Rashmi Aich and Subhranshu Sahu)

((Bipasha.Dey@thomsonreuters.com;))