Company: BLLN
Filing Date: 2025-08-11
Form Type: DRS/A
Source: 0000950123-25-007483
Chunk: 288

Company: BillionToOne, Inc.
Filing Date: 2025-08-11
Form: DRS/A
Chunk 288
---
, are attributable to a permanent establishment or fixed base maintained by the non-U.S.holder in the United States, are not subject to U.S. withholding tax. To obtain this exemption, a non-U.S.holder must provide the applicable withholding agent with an IRS Form W-8ECI(or any successor or substitute form thereof) properly certifying such exemption, and periodically update such certification. Such effectively connected dividends, although not subject to withholding tax, are taxed at the same U.S. federal income tax rates applicable to U.S. persons, net of certain deductions and credits. In addition to being taxed at U.S. federal income tax rates, dividends received by a corporate non-U.S.holder that are effectively connected with a U.S. trade or business of the corporate non-U.S.holder may also be subject to a branch profits tax at a rate of 30% or such lower rate as may be specified by an applicable tax treaty. Gain on sale or other disposition of Class A common stock Subject to the discussion below under the section titled “—Backup withholding and information reporting” and “—Foreign Account Tax Compliance Act,” non-U.S.holders will generally not be subject to U.S. federal income tax on any gains realized on the sale, exchange or other disposition of our Class A common stock unless:

| • |     | the gain (1) is effectively connected with the conduct by the non-U.S. holder                                                                                                               
 of a U.S. trade or business and (2) if required by an applicable income tax treaty between the United States and the non-U.S. holder’s country of residence, is attributable to a permanent 
 establishment or fixed base maintained by the non-U.S. holder in the United States (in which case the special rules described below apply);                                                 |

| • |     | the non-U.S. holder is an individual who is present in the United States for 183                                                                                                                                                                     
 days or more in the taxable year of the sale, exchange or other disposition of our Class A common stock, and certain other requirements are met (in which case the gain would be subject to a flat 30% tax, or such reduced rate as may be specified 
 by an applicable income tax treaty, which may be offset by U.S. source capital losses, even though the individual is not considered a resident of the United States), provided that the non-U.S. Holder has                                          
 timely filed U.S. federal income tax returns with respect to such losses; or                                                                                                                                                                         |

| • |     | the