BLLN BillionToOne, Inc.

“We did not design and maintain effective user access controls to ensure appropriate segregation of duties and to adequately restrict user and privileged access to appropriate personnel in creating and posting journal entries.”

“We did not design and maintain effective controls to appropriately analyze, account for, and present and disclose amounts related to certain financial instruments. Specifically, we did not design and maintain controls to appropriately analyze, account for, and present and disclose amounts related to outstanding common stock warrants.”

“We did not design and maintain an effective control environment commensurate with our financial reporting requirements. Specifically, we lack a sufficient complement of resources with the appropriate knowledge, experience, and training to appropriately analyze, record and disclose accounting matters commensurate with our accounting and reporting requirements.”

“Based on such evaluation, our Chief Executive Officer and Chief Financial Officer have concluded that these disclosure controls and procedures were not effective at the reasonable assurance level as of September 30, 2026 due to the material weaknesses in our internal control over financial reporting as described below.”

“our ability to remediate the material weaknesses in our internal control over financial reporting or additional material weaknesses or other deficiencies in the future or to maintain effective disclosure controls and procedures and internal control over financial reporting”